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            <liveTestFlag>LIVE</liveTestFlag>



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            <issuerCik>0001013857</issuerCik>
            <issuerName>PEGASYSTEMS INC.</issuerName>
            <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>EFSTATHIOS A KOUNINIS</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
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        <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>
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            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>248</noOfUnitsSold>
            <aggregateMarketValue>13020.00</aggregateMarketValue>
            <noOfUnitsOutstanding>83555919</noOfUnitsOutstanding>
            <approxSaleDate>12/14/2023</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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            <paymentDate>09/03/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
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        <securitiesToBeSold>
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            <acquiredDate>12/01/2023</acquiredDate>
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            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>77</amountOfSecuritiesAcquired>
            <paymentDate>09/01/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>12/02/2023</acquiredDate>
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            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>40</amountOfSecuritiesAcquired>
            <paymentDate>09/02/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>12/06/2023</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted stock vesting under a registered plan</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>73</amountOfSecuritiesAcquired>
            <paymentDate>09/06/2023</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
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        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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                <address>
                    <ns2:street1>One Main Street</ns2:street1>
                    <ns2:city>Cambridge</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02142</ns2:zipCode>
                </address>
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            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>11/22/2023</saleDate>
            <amountOfSecuritiesSold>4723</amountOfSecuritiesSold>
            <grossProceeds>247486.14</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>12/14/2023</noticeDate>
            <planAdoptionDates/>
            <signature>/s/ Efstathios Kouninis</signature>
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144
0001353196
XXXXXXXX
LIVE
0001013857
PEGASYSTEMS INC.
001-11859
One Main Street
Cambridge
MA
02142
(617) 374-9600
EFSTATHIOS A KOUNINIS
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
248
13020.00
83555919
12/14/2023
NASDAQ
Common
12/03/2023
Restricted stock vesting under a registered plan
Issuer
N
58
09/03/2023
Not Applicable
Common
12/01/2023
Restricted stock vesting under a registered plan
Issuer
N
77
09/01/2023
Not Applicable
Common
12/02/2023
Restricted stock vesting under a registered plan
Issuer
N
40
09/02/2023
Not Applicable
Common
12/06/2023
Restricted stock vesting under a registered plan
Issuer
N
73
09/06/2023
Not Applicable
N
EFSTATHIOS A KOUNINIS
One Main Street
Cambridge
MA
02142
Common
11/22/2023
4723
247486.14
12/14/2023
/s/ Efstathios Kouninis