    <SEC-DOCUMENT>0001558370-22-000225-index.html : 20220112
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    <ACCEPTANCE-DATETIME>20220111210905
    ACCESSION NUMBER:		0001558370-22-000225
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		17
    CONFORMED PERIOD OF REPORT:	20220110
    ITEM INFORMATION:		Entry into a Material Definitive Agreement
    ITEM INFORMATION:		Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20220112
    DATE AS OF CHANGE:		20220111

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			FRANKLIN STREET PROPERTIES CORP /MA/
    		CENTRAL INDEX KEY:			0001031316
    		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
    		IRS NUMBER:				042724223
    		STATE OF INCORPORATION:			MA
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-32470
    		FILM NUMBER:		22525320

    	BUSINESS ADDRESS:
    		STREET 1:		401 EDGEWATER PLACE
    		STREET 2:		STE 200
    		CITY:			WAKEFIELD
    		STATE:			MA
    		ZIP:			01880
    		BUSINESS PHONE:		7815571300

    	MAIL ADDRESS:
    		STREET 1:		401 EDGEWATER PLACE
    		STREET 2:		STE 200
    		CITY:			WAKEFIELD
    		STATE:			MA
    		ZIP:			01880

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	FRANKLIN STREET PARTNERS LP
    		DATE OF NAME CHANGE:	20010301
    </SEC-HEADER>
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    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>fsp-20220110x8k.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: fsp-20220110x8k.htm

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    <TYPE>EX-10.1
    <SEQUENCE>2
    <FILENAME>fsp-20220110xex10d1.htm
    <DESCRIPTION>EX-10.1
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    <FILENAME>fsp-20220110xex10d1002.jpg
    <DESCRIPTION>GRAPHIC
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    <FILENAME>fsp-20220110xex10d1001.jpg
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    <DOCUMENT>
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    <SEQUENCE>7
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    <DESCRIPTION>EX-101.SCH
    <TEXT>
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    <SEQUENCE>8
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    <DESCRIPTION>EX-101.LAB
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    <SEQUENCE>9
    <FILENAME>fsp-20220110_pre.xml
    <DESCRIPTION>EX-101.PRE
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    <SEQUENCE>10
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    <SEQUENCE>11
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    <TYPE>EXCEL
    <SEQUENCE>12
    <FILENAME>Financial_Report.xlsx
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    <SEQUENCE>13
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    <SEQUENCE>14
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    <TEXT>
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    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>15
    <FILENAME>FilingSummary.xml
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    <TEXT>
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    <DOCUMENT>
    <TYPE>JSON
    <SEQUENCE>17
    <FILENAME>MetaLinks.json
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    <TEXT>
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    <TYPE>ZIP
    <SEQUENCE>18
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