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                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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            <secFileNumber>001-11859</secFileNumber>
            <issuerAddress>
                <ns2:street1>One Main Street</ns2:street1>
                <ns2:city>Cambridge</ns2:city>
                <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                <ns2:zipCode>02142</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(617) 374-9600</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>KENNETH STILLWELL JR.</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>4744</noOfUnitsSold>
            <aggregateMarketValue>405705.93</aggregateMarketValue>
            <noOfUnitsOutstanding>85753808</noOfUnitsOutstanding>
            <approxSaleDate>11/06/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
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            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/06/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of options under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>4744</amountOfSecuritiesAcquired>
            <paymentDate>11/06/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>KENNETH STILLWELL JR.</name>
                <address>
                    <ns2:street1>One Main Street</ns2:street1>
                    <ns2:city>Cambridge</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02142</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>10/25/2024</saleDate>
            <amountOfSecuritiesSold>5792</amountOfSecuritiesSold>
            <grossProceeds>458442.01</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>KENNETH STILLWELL JR.</name>
                <address>
                    <ns2:street1>One Main Street</ns2:street1>
                    <ns2:city>Cambridge</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02142</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>10/01/2024</saleDate>
            <amountOfSecuritiesSold>1000</amountOfSecuritiesSold>
            <grossProceeds>73170.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>KENNETH STILLWELL JR.</name>
                <address>
                    <ns2:street1>One Main Street</ns2:street1>
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                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02142</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>09/03/2024</saleDate>
            <amountOfSecuritiesSold>3000</amountOfSecuritiesSold>
            <grossProceeds>211230.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>KENNETH STILLWELL JR.</name>
                <address>
                    <ns2:street1>One Main Street</ns2:street1>
                    <ns2:city>Cambridge</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02142</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>08/21/2024</saleDate>
            <amountOfSecuritiesSold>3019</amountOfSecuritiesSold>
            <grossProceeds>203923.19</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>11/06/2024</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Kenneth Stillwell</signature>
        </noticeSignature>
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144
0001680115
XXXXXXXX
LIVE
0001013857
PEGASYSTEMS INC.
001-11859
One Main Street
Cambridge
MA
02142
(617) 374-9600
KENNETH STILLWELL JR.
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
4744
405705.93
85753808
11/06/2024
NASDAQ
Common
11/06/2024
Exercise of options under a registered plan
Issuer
N
4744
11/06/2024
Cash
N
KENNETH STILLWELL JR.
One Main Street
Cambridge
MA
02142
Common
10/25/2024
5792
458442.01
KENNETH STILLWELL JR.
One Main Street
Cambridge
MA
02142
Common
10/01/2024
1000
73170.00
KENNETH STILLWELL JR.
One Main Street
Cambridge
MA
02142
Common
09/03/2024
3000
211230.00
KENNETH STILLWELL JR.
One Main Street
Cambridge
MA
02142
Common
08/21/2024
3019
203923.19
11/06/2024
/s/ Kenneth Stillwell