<HTML>
<HEAD>
     <TITLE></TITLE>
</HEAD>
<BODY STYLE="font: 10pt Times New Roman, Times, Serif">

<P STYLE="margin: 0"></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/16pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION</B></P>

<P STYLE="font: 10pt/14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>WASHINGTON, D.C. 20549</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 18pt/20pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>FORM 8-K</B></P>

<P STYLE="font: 10pt/14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>CURRENT REPORT<BR>
PURSUANT TO SECTION 13 OR 15(D) OF<BR>
THE SECURITIES EXCHANGE ACT OF 1934</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>Date of Report (Date of earliest event
reported): February 24, 2012</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 18pt/26pt Times New Roman, Times, Serif; margin: 0; text-align: center"><FONT STYLE="font-family: Times New Roman, Times, Serif"><B>Rio
Bravo Oil, Inc.</B></FONT><B> </B></P>

<P STYLE="font: 10pt/14pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>(Formerly known as Soton Holdings Group,
Inc.)</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">(Exact Name of Registrant as Specified
in its Charter)</P>

<TABLE ALIGN="CENTER" CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif">
<TR>
    <TD STYLE="width: 25%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 1%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 25%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 1%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 25%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center; border-bottom: Black 1pt solid">Nevada</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center; border-bottom: Black 1pt solid">000-54564</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center; border-bottom: Black 1pt solid">42-1771917</TD></TR>
<TR>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">(State or Other Jurisdiction of Incorporation) &nbsp;&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">(Commission File No.)</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">(I.R.S. Employer Identification No.)</TD></TR>
<TR>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">&nbsp;</TD></TR>
<TR>
    <TD COLSPAN="3" STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center; border-bottom: Black 1pt solid">5858 Westheimer, Suite 699, Houston, TX</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center; border-bottom: Black 1pt solid">77057</TD></TR>
<TR>
    <TD COLSPAN="3" STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">(Address of Principal Executive Offices)</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; text-align: center">(Zip Code)</TD></TR>
</TABLE>
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">Registrant&rsquo;s telephone number, including
area code: [insert]</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">Soton Holdings Group, Inc.</P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: center"><U>180 Madison Avenue, Suite 1702,
New York, NY 10016</U></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">(Former name or former address, if changed
since last report)</P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: center">(Address of Principal Offices)</P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt">Check the appropriate box below if the Form 8-K filing
is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General
Instruction A.2. below):</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif">
<TR>
    <TD STYLE="width: 3%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 1%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="width: 96%; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR STYLE="vertical-align: bottom">
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%"><FONT STYLE="font-family: Times New Roman, Times, Serif"></FONT><FONT STYLE="font-family: Wingdings 2">&pound;</FONT></TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">Written communications pursuant to Rule&nbsp;425 under the Securities Act (17 CFR 230.425)</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%"><FONT STYLE="font-family: Wingdings 2">&pound;</FONT><FONT STYLE="font-family: Times New Roman, Times, Serif"> </FONT></TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">Soliciting material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR 240.14a-12)</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; font-family: Wingdings 2">&pound;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">Pre-commencement communications pursuant to Rule&nbsp;14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD></TR>
<TR>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%; font-family: Wingdings 2">&pound;</TD>
    <TD STYLE="vertical-align: bottom; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="vertical-align: top; padding-top: 0.75pt; padding-right: 0.75pt; padding-left: 0.75pt; line-height: 115%">Pre-commencement communications pursuant to Rule&nbsp;13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</TD></TR>
</TABLE>
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0"></P>

<!-- Field: Page; Sequence: 1 -->
    <DIV STYLE="margin-top: 12pt; margin-bottom: 6pt; border-bottom: Black 1pt solid"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font-size: 10pt"><TR><TD STYLE="text-align: center; width: 100%">&nbsp;</TD></TR></TABLE></DIV>
    <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 12pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 50%">&nbsp;</TD><TD STYLE="text-align: right; width: 50%"></TD></TR></TABLE></DIV>
    <!-- Field: /Page -->
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>TABLE OF CONTENTS</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 10pt">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 10pt"></P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 12%; line-height: 115%">Item 1.01&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; width: 88%">Entry into a Material Definitive Agreement</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%">Item 2.03</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%">Item 9.01</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%">Financial Statements and Exhibits</TD></TR>
</TABLE>


<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 10pt">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 10pt">SIGNATURES</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 10pt">EXHIBIT INDEX</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0"></P>

<!-- Field: Page; Sequence: 2 -->
    <DIV STYLE="margin-top: 12pt; margin-bottom: 6pt; border-bottom: Black 1pt solid"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font-size: 10pt"><TR><TD STYLE="text-align: center; width: 100%">&nbsp;</TD></TR></TABLE></DIV>
    <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 12pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 50%">&nbsp;</TD><TD STYLE="text-align: right; width: 50%"></TD></TR></TABLE></DIV>
    <!-- Field: /Page -->
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 12pt"><B>Item 1.01&#9;Entry into a Material Definitive Agreement</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B></B></P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: justify">On February 24, 2012, Rio Bravo
Oil, Inc. <FONT STYLE="color: black">(f/k/a/ Soton Holdings Group, Inc.), a Nevada corporation (the &ldquo;Company&rdquo;) entered
into two (2) convertible promissory notes (individually, a &ldquo;Note&rdquo; and collectively, the &ldquo;Notes&rdquo;) in the
amounts of $1,000,000 and $1,500,000, respectively ($2,500,000 in the aggregate) payable to </FONT>Personalvorsorge der Autogrill
Schweiz AG and Hohenplan Privatstiftung, respectively. Each Note is due and payable by its terms on or before December 31, 2014
and bears interest at a rate of eight percent (8%) per annum. The outstanding principal amount of each Note, together with accrued
interest, is convertible, in whole or in part, at the sole discretion of each respective payee, into shares of Company Common Stock
calculated as follows: (a) the principal amount of the Note which is converted divided by the Original Principal Amount (as defined
in the Notes) multiplied by One Million (1,000,000) as to the $1,000,000 Note or multiplied by One Million Five Hundred Thousand
(1,500,000) as to the $1,500,000 Note; plus (b) the amount of any accrued interest on the amount converted through the date of
conversion (calculated on a 360 day year comprising 30 day months) multiplied by one. The conversion ratio is subject to adjustment
upon the occurrence of certain events. In addition, the Notes (together with any accrued interest thereon) shall be automatically
converted to Company Common Stock at any time after March 1, 2013, should the shares of the Company&rsquo;s Common Stock trade
at a price of over $2.50 per share (as adjusted for stock splits or other events which would result in an adjustment of the number
of shares of Company Common Stock issuable pursuant to the terms of the Notes) for a period in excess of thirty (30) consecutive
trading days, based upon the following calculation: (a) the then outstanding principal amount of the Note multiplied by one (1);
plus (b) the amount of any accrued but unpaid interest on the Note through the date of conversion (calculated on a 360 day year
comprising 30 day months) multiplied by one. Each of the Notes carries piggyback registration rights.</P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: justify">The proceeds of the Notes will
be used for working capital and general corporate purposes.</P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: justify">Copies of the Notes are attached
hereto as Exhibits 2.1 and 2.2, respectively.</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 0.75in; text-align: justify; text-indent: -0.75in"><FONT STYLE="color: black"><B>Item
2.03&#9;</B></FONT><B>Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.</B></P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: justify"><B></B></P>

<P STYLE="font: 10pt/115% Times New Roman, Times, Serif; margin: 0 0 10pt; text-align: justify">Please refer to Item 2.01, above.</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Item&nbsp;9.01 Financial Statements
and Exhibits.</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in">(d)&nbsp;Exhibits</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 17%; line-height: 115%; text-decoration: underline; text-align: justify">NUMBER</TD>
    <TD STYLE="width: 83%; padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-decoration: underline; text-align: justify">DESCRIPTION</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%; text-align: justify">2.1</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify"><FONT STYLE="letter-spacing: -0.3pt">Promissory Note in the face amount of $1,000,000 dated February 24, 2012 between the Company and </FONT>Personalvorsorge der Autogrill Schweiz AG<FONT STYLE="letter-spacing: -0.3pt">.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%; text-align: justify">2.2</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify"><FONT STYLE="letter-spacing: -0.3pt">Promissory Note in the face amount of $1,500,000 dated February 24, 2012 between the Company and </FONT>Hohenplan Privatstiftung<FONT STYLE="letter-spacing: -0.3pt">.</FONT></TD></TR>
</TABLE>


<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"></P>

<!-- Field: Page; Sequence: 3 -->
    <DIV STYLE="margin-top: 12pt; margin-bottom: 6pt; border-bottom: Black 1pt solid"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font-size: 10pt"><TR><TD STYLE="text-align: center; width: 100%">&nbsp;</TD></TR></TABLE></DIV>
    <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 12pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 50%">&nbsp;</TD><TD STYLE="text-align: right; width: 50%"></TD></TR></TABLE></DIV>
    <!-- Field: /Page -->
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><FONT STYLE="letter-spacing: -0.3pt">&nbsp;</FONT></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center"><B>SIGNATURES</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to the requirements of the Securities and Exchange Act of 1934, the registrant has duly caused this report to be signed on its
behalf by the undersigned hereunto duly authorized.</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><B>Rio Bravo Oil, Inc.</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"><I></I></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">By: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<I><U>/s/
Carlos E. Buchanan II</U></I></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Name: Carlos E. Buchanan II</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Title: &nbsp;&nbsp;Chief Financial Officer</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">Dated: March 2, 2012</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"></P>

<!-- Field: Page; Sequence: 4 -->
    <DIV STYLE="margin-top: 12pt; margin-bottom: 6pt; border-bottom: Black 1pt solid"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font-size: 10pt"><TR><TD STYLE="text-align: center; width: 100%">&nbsp;</TD></TR></TABLE></DIV>
    <DIV STYLE="page-break-before: always; margin-top: 6pt; margin-bottom: 12pt"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%"><TR><TD STYLE="text-align: left; width: 50%">&nbsp;</TD><TD STYLE="text-align: right; width: 50%"></TD></TR></TABLE></DIV>
    <!-- Field: /Page -->
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 3pt 0; text-align: center"><B>EXHIBIT LIST</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-indent: -0.4in">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-align: justify; text-indent: -0.4in"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"></P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 17%; line-height: 115%; text-decoration: underline; text-align: justify">NUMBER</TD>
    <TD STYLE="width: 83%; padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-decoration: underline; text-align: justify">DESCRIPTION</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%; text-align: justify">2.1</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify"><FONT STYLE="letter-spacing: -0.3pt">Promissory Note in the face amount of $1,000,000 dated February 24, 2012 between the Company and </FONT>Personalvorsorge der Autogrill Schweiz AG<FONT STYLE="letter-spacing: -0.3pt">.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 115%; text-align: justify">2.2</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; line-height: 115%; text-align: justify"><FONT STYLE="letter-spacing: -0.3pt">Promissory Note in the face amount of $1,500,000 dated February 24, 2012 between the Company and </FONT>Hohenplan Privatstiftung<FONT STYLE="letter-spacing: -0.3pt">.</FONT></TD></TR>
</TABLE>


<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0; text-align: justify"></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-align: justify; text-indent: -0.4in">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-align: justify; text-indent: -0.4in"></P>

<!-- Field: Page; Sequence: 5; Options: Last -->
    <DIV STYLE="margin-top: 12pt; margin-bottom: 6pt; border-bottom: Black 1pt solid"><TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font-size: 10pt"><TR><TD STYLE="text-align: center; width: 100%">&nbsp;</TD></TR></TABLE></DIV>
    <!-- Field: /Page -->
<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-align: justify; text-indent: -0.4in">&nbsp;</P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0 0 0 27.5pt; text-align: justify; text-indent: -0.4in">&nbsp;</P>



<P STYLE="margin: 0"></P>

</BODY>
</HTML>
[{"type": "8-K", "sequence": "1", "filename": "v304611_8k.htm", "secsgml_size_bytes": 27703}]
{"company-data": {"conformed-name": "Rio Bravo Oil, Inc.", "cik": "0001502774", "assigned-sic": "1311", "irs-number": "421771917", "state-of-incorporation": "NV", "fiscal-year-end": "0930"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-54564", "film-number": "12662797"}, "business-address": {"street1": "180 MADISON AVENUE", "street2": "SUITE 1702", "city": "NEW YORK", "state": "NY", "zip": "10016", "phone": "1-281-724-3810"}, "mail-address": {"street1": "180 MADISON AVENUE", "street2": "SUITE 1702", "city": "NEW YORK", "state": "NY", "zip": "10016"}, "former-company": {"former-conformed-name": "Soton Holdings Group, Inc.", "date-changed": "20101005"}}
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(D) OF
THE SECURITIES EXCHANGE ACT OF 1934
Date of Report (Date of earliest event
reported): February 24, 2012
Rio
Bravo Oil, Inc.
(Formerly known as Soton Holdings Group,
Inc.)
(Exact Name of Registrant as Specified
in its Charter)
Nevada
000-54564
42-1771917
(State or Other Jurisdiction of Incorporation)
(Commission File No.)
(I.R.S. Employer Identification No.)
5858 Westheimer, Suite 699, Houston, TX
77057
(Address of Principal Executive Offices)
(Zip Code)
Registrant's telephone number, including
area code: [insert]
Soton Holdings Group, Inc.
180 Madison Avenue, Suite 1702,
New York, NY 10016
(Former name or former address, if changed
since last report)
(Address of Principal Offices)
Check the appropriate box below if the Form 8-K filing
is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General
Instruction A.2. below):
£
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
£
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
£
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
£
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
TABLE OF CONTENTS
Item 1.01
Entry into a Material Definitive Agreement
Item 2.03
Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.
Item 9.01
Financial Statements and Exhibits
SIGNATURES
EXHIBIT INDEX
Item 1.01	Entry into a Material Definitive Agreement
On February 24, 2012, Rio Bravo
Oil, Inc.
(f/k/a/ Soton Holdings Group, Inc.), a Nevada corporation (the "Company") entered
into two (2) convertible promissory notes (individually, a "Note" and collectively, the "Notes") in the
amounts of $1,000,000 and $1,500,000, respectively ($2,500,000 in the aggregate) payable to
Personalvorsorge der Autogrill
Schweiz AG and Hohenplan Privatstiftung, respectively. Each Note is due and payable by its terms on or before December 31, 2014
and bears interest at a rate of eight percent (8%) per annum. The outstanding principal amount of each Note, together with accrued
interest, is convertible, in whole or in part, at the sole discretion of each respective payee, into shares of Company Common Stock
calculated as follows: (a) the principal amount of the Note which is converted divided by the Original Principal Amount (as defined
in the Notes) multiplied by One Million (1,000,000) as to the $1,000,000 Note or multiplied by One Million Five Hundred Thousand
(1,500,000) as to the $1,500,000 Note; plus (b) the amount of any accrued interest on the amount converted through the date of
conversion (calculated on a 360 day year comprising 30 day months) multiplied by one. The conversion ratio is subject to adjustment
upon the occurrence of certain events. In addition, the Notes (together with any accrued interest thereon) shall be automatically
converted to Company Common Stock at any time after March 1, 2013, should the shares of the Company's Common Stock trade
at a price of over $2.50 per share (as adjusted for stock splits or other events which would result in an adjustment of the number
of shares of Company Common Stock issuable pursuant to the terms of the Notes) for a period in excess of thirty (30) consecutive
trading days, based upon the following calculation: (a) the then outstanding principal amount of the Note multiplied by one (1);
plus (b) the amount of any accrued but unpaid interest on the Note through the date of conversion (calculated on a 360 day year
comprising 30 day months) multiplied by one. Each of the Notes carries piggyback registration rights.
The proceeds of the Notes will
be used for working capital and general corporate purposes.
Copies of the Notes are attached
hereto as Exhibits 2.1 and 2.2, respectively.
Item
2.03
Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.
Please refer to Item 2.01, above.
Item 9.01 Financial Statements
and Exhibits.
(d) Exhibits
NUMBER
DESCRIPTION
2.1
Promissory Note in the face amount of $1,000,000 dated February 24, 2012 between the Company and
Personalvorsorge der Autogrill Schweiz AG
.
2.2
Promissory Note in the face amount of $1,500,000 dated February 24, 2012 between the Company and
Hohenplan Privatstiftung
.
SIGNATURES
Pursuant
to the requirements of the Securities and Exchange Act of 1934, the registrant has duly caused this report to be signed on its
behalf by the undersigned hereunto duly authorized.
Rio Bravo Oil, Inc.
By:
/s/
Carlos E. Buchanan II
Name: Carlos E. Buchanan II
Title:   Chief Financial Officer
Dated: March 2, 2012
EXHIBIT LIST
NUMBER
DESCRIPTION
2.1
Promissory Note in the face amount of $1,000,000 dated February 24, 2012 between the Company and
Personalvorsorge der Autogrill Schweiz AG
.
2.2
Promissory Note in the face amount of $1,500,000 dated February 24, 2012 between the Company and
Hohenplan Privatstiftung
.