As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SFO - UNIDENTIFIED NOISE REPORTED IN COCKPIT DURING CLIMB. ACFT RETURNED TO STA WITHOUT INCIDENT. MAINTENANCE INSPECTED ACFT TO LOCATE SOURCE OF NOISE. FOUND 6 INCH PORTION OF 'PRC' SEAL LOOSE AT TOP OF CAPTAIN'S WINDSHIELD. REMOVED EXCESS MATERIAL. ACFT RETURNED TO SERVICE. (W)