CORPORATE SMT BELIEVES HE HEARS CLRNC FOR TKOF WHEN IN POS AND HOLD. CLRNC ACTUALLY FOR ACFT ON INTXN TKOF. TKOF ABORTED.

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BOS USING RWY 22R FOR DEP. I WAS #1 AT FULL LENGTH. I WAS TOLD TO TAXI INTO POS AND HOLD. I ACKNOWLEDGED AND AFTER APPROX 10 SECONDS; THE TWR CLRED AN ACFT ON RWY 22R FOR TKOF. I ACKNOWLEDGED CLRED AN ACFT FOR TKOF AND I PROCEEDED. JUST AS I BROKE GND; TWR ASKED ME 'WHAT AM I DOING.' I CLOSED THROTTLES; LANDED AND STOPPED. WHEN I WAS STOPPING; I OBSERVED AN ACFT APPROX 4000 FT FURTHER DOWN RWY 22R. I THOUGHT THE TKOF CLRNC WAS FOR ME. I HAD NOT HEARD ANY ACFT BEING CLRED FOR TKOF FROM AN INTXN FOR THE ESTIMATED 20 MINS IT TOOK ME TO GET TO THE APCH END OF RWY 22R. I ASKED THE TWR BY TELEPHONE WHY HE DID NOT CHALLENGE ME. THEY SAID THAT WHEN THEY PLAYED THE TAPE BACK MY TKOF ACKNOWLEDGEMENT WAS BLOCKED BY THE TKOF ACKNOWLEDGEMENT OF THE OTHER ACFT THAT HAD THE RIGHT-OF- WAY. BOS WAS USING RWY 22L FOR LNDGS AND ALSO A WDB WAS WAITING TO USE RWY 22L FOR TKOF BECAUSE OF HIS WT. I HAD NO IDEA BOS WAS GOING TO USE INTERSECTING RWY 22R FOR TKOF; ALSO MY MISTAKE. IF I MAY RESPECTFULLY MAKE A SUGGESTION TO PREVENT A FURTHER OCCURRENCE. TWR SHOULD ADVISE ACFT POSITIONING FULL LENGTH TO BE ADVISED AN ACFT IS POSITIONING ON RWY 22R FROM TXWY T AND THAT ACFT FULL LENGTH WILL BE #2 FOR DEP ON RWY 22R.