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    CONFORMED PERIOD OF REPORT:	20240531
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    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			Flaherty & Crumrine PREFERRED & INCOME OPPORTUNITY FUND INC
    		CENTRAL INDEX KEY:			0000882071
    		ORGANIZATION NAME:
    		IRS NUMBER:				954355600
    		STATE OF INCORPORATION:			MD
    		FISCAL YEAR END:			1130

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    		SEC ACT:		1940 Act
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    	BUSINESS ADDRESS:
    		STREET 1:		301 E COLORADO BLVD STE 720
    		STREET 2:		C/O FLAHERTY & CRUMRINE INC
    		CITY:			PASADENA
    		STATE:			CA
    		ZIP:			91101
    		BUSINESS PHONE:		(626) 795-7300

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    		STREET 1:		301 COLORADO BLVD STE 800
    		STREET 2:		C/O FLAHERTY & CRUMRINE INC
    		CITY:			PASADENA
    		STATE:			CA
    		ZIP:			91101

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    		FORMER CONFORMED NAME:	Flaherty & Crumrine PREFERRED INCOME OPPORTUNITY FUND INC
    		DATE OF NAME CHANGE:	20050708

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    		FORMER CONFORMED NAME:	PREFERRED INCOME OPPORTUNITY FUND INC
    		DATE OF NAME CHANGE:	19920929
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