Narrative:

Citation 500 (Y) direct oth at FL280 was exiting my airspace to the north when a B737 (X) departing smf on the frogo 6 departure sebound, called on asking for a higher altitude. I climbed air carrier X to FL270 (requesting FL290) to stay vertically clear of aircraft Y. 2 mins after the aircraft Y data block was dropped outside of my sector, I climbed air carrier X to FL290 to get above inbound traffic to sfo descending to FL240. Approximately 1 min later, air carrier X descended from FL275 to FL272 responding to an RA TCASII alert, then climbed back up to FL290. Conflict alert activated just as separation was lost. Even though the data block had been dropped, a limited data block was still displayed showing altitude and position of aircraft Y. This occurred outside of my airspace and a point-out had been made to the other sector so I was inclined to discount the limited data block, thinking it was the other sector's traffic. The data block should not have been dropped until the traffic (air carrier X) was clear.

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Original NASA ASRS Text

Title: ZOA CTLR DROPS C500 DATA TAG AS ACFT DEPARTS HIS AIRSPACE, AND CLBS A B737 WHICH CONFLICTS WITH THE C500.

Narrative: CITATION 500 (Y) DIRECT OTH AT FL280 WAS EXITING MY AIRSPACE TO THE N WHEN A B737 (X) DEPARTING SMF ON THE FROGO 6 DEP SEBOUND, CALLED ON ASKING FOR A HIGHER ALT. I CLBED ACR X TO FL270 (REQUESTING FL290) TO STAY VERTLY CLR OF ACFT Y. 2 MINS AFTER THE ACFT Y DATA BLOCK WAS DROPPED OUTSIDE OF MY SECTOR, I CLBED ACR X TO FL290 TO GET ABOVE INBOUND TFC TO SFO DSNDING TO FL240. APPROX 1 MIN LATER, ACR X DSNDED FROM FL275 TO FL272 RESPONDING TO AN RA TCASII ALERT, THEN CLBED BACK UP TO FL290. CONFLICT ALERT ACTIVATED JUST AS SEPARATION WAS LOST. EVEN THOUGH THE DATA BLOCK HAD BEEN DROPPED, A LIMITED DATA BLOCK WAS STILL DISPLAYED SHOWING ALT AND POS OF ACFT Y. THIS OCCURRED OUTSIDE OF MY AIRSPACE AND A POINT-OUT HAD BEEN MADE TO THE OTHER SECTOR SO I WAS INCLINED TO DISCOUNT THE LIMITED DATA BLOCK, THINKING IT WAS THE OTHER SECTOR'S TFC. THE DATA BLOCK SHOULD NOT HAVE BEEN DROPPED UNTIL THE TFC (ACR X) WAS CLR.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.