As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A/C WAS ENROUTE AT FL260, WINDSHIELD ANTI-ICE WAS SELECTED ON AND WAS ON FOUR 1 1/2 HOURS WHEN A LOUD CRACK WAS HEARD AND THE PILOTS WINDSHIELD SHATTERED THE INNER PANE INTO PEA SIZED PIECES. CREW FOLLOWED AIRCRAFT ABNORMAL PROCEDURES AND DESCENDED BELOW 25,000 FEET AND KEEP CABIN PSI BETWEEN 2 AND 4.6. OAT AT TIME WAS -35C. AIRCRAFT WAS FLOWN BACK TO HOME BASE.