A CPR SMT MAY HAVE ENTERED CLASS B AIRSPACE.

Narrative

ACFT WAS INITIALLY ON AN IFR FLT PLAN ON V-287 PROCEEDING TO LOFAL INTXN. CLRNC WAS FOR VFR ON TOP. SEA APCH ADVISED TO EXPEDITE DSCNT FOR ARRIVING JET TFC INBOUND TO SEA. COPLT ADVISED ATC TFC IN SIGHT. OUR DEST WAS PAE. AS WE APCHED LOFAL; WE GOT VISUAL WITH THE ARPT. ATC ADVISED TO MAINTAIN VISUAL CONTACT WITH JET TFC AND REMAIN CLR OF 'CBA' (CLASS B AIRSPACE). AT THE TIME; WE HAD CANCELED IFR AND STARTED A VFR DSCNT. AS I LEVELED OFF AT 10000 MSL (TOP OF CLASS B AIRSPACE); ATC ASKED ALT. COPLT RPTED 9800 FROM HIS ALTIMETER. MY ALTIMETER SAID 10000. ATC ADVISED CLASS B AIRSPACE WAS 8500-10000 FT. JET ACFT DSNDING INTO CLASS B AIRSPACE HAD MY ACFT IN SIGHT ALSO. PASSING LOFAL INTXN; SEA APCH HANDED US OFF TO ZSE FOR DSCNT INTO PAE. THE PROB OCCURRED BECAUSE I WAS NOT PROPERLY AWARE OF THE CLASS B AIRSPACE BOUNDARIES IN THE AREA OF LOFAL INTXN. ALTHOUGH THERE WAS NO DANGER OF A COLLISION WITH THE CONFLICTING TFC; IT SHOULD BE NOTED THAT A PLT NEEDS TO BE AWARE OF ALL ASPECTS OF FLT. SEA APCH'S NORMAL PROC FOR IFR CANCELLATION NEAR THE CLASS B AIRSPACE IS TO AUTHORIZE VFR DSCNT THROUGH AIRSPACE. BOTH ACFT HAD VISUAL CONTACT. ONE OTHER POINT; THE CTLR'S USE OF THE TERM 'CBA.' I DON'T BELIEVE THAT IS ON OFFICIAL TERM FROM THE ATC GLOSSARY. IT'S USE WAS CONFUSING FOR A TIME.