X0303 4 2008-09-16 0 0001360886 OSIRIS THERAPEUTICS, INC. OSIR 0001008317 FRIEDLI PETER C/O OSIRIS THERAPEUTICS, INC. 7015 ALBERT EINSTEIN DRIVE COLUMBIA MD 21046 1 0 1 1 Chairman Common Stock 9880371 D Common Stock 2008-09-16 4 J 0 1000000 0 D 3964245 I see Note 2 Decrease in beneficial ownership due to the termination of investment control over securities directly owned by US Venture 05, Inc. The Reporting Person holds indirect beneficial ownership of 625 shares held by his mother and 3,963,620 shares owned by Venturetec, Inc. The Reporting Person holds approximately a 3% interest in Venturetec, Inc. and serves as its president. The Reporting Person disclaims beneficial interest in the shares held by his mother and disclaims beneficial interest in the shares held by Venturetec, Inc. beyond the extent of his pecuniary interest therein. Peter Friedli 2008-09-18