X0303 4 2010-12-17 0001111928 IPG PHOTONICS CORP IPGP 0001130421 GAPONTSEV VALENTIN P C/O IPG PHOTONICS CORPORATION 50 OLD WEBSTER ROAD OXFORD MA 01540 1 1 1 0 CEO & Chairman of the Board Common Stock 2010-12-17 4 S 0 7200000 26.64 D 3902931 D Common Stock 2010-12-17 5 G 0 800000 0 D 3102931 D Common Stock 2010-12-17 4 S 0 2880154 D 7504002 I By IP Fibre Devices (UK) Ltd. Common Stock 2010-12-17 5 G 0 720039 0 D 7504002 I By IP Fibre Devices (UK) Ltd. Shares sold by the Reporting Person to The Valentin Gapontsev Trust I (the "Trust"), an irrevocable trust for benefit of the Reporting Person's descendants, on December 17, 2010. The transaction was done for estate planning purposes. Shares gifted by the Reporting Person to the Trust on December 17, 2010. The transaction was done for estate planning purposes. The reported securities are held by IP Fibre Devices (UK) Ltd. ("IPFD"). On December 17, 2010, the Reporting Person sold shares representing 38.4% of the total shares outstanding of IPFD to the Trust. The aggregate purchase price for the shares of IPFD that the Reporting Person sold to the Trust was $43,378,560. The transaction was done for estate planning purposes. The Reporting Person disclaims beneficial ownership of the Issuer's common stock held by IPFD, except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of the beneficial ownership of all the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. The reported securities are held by IPFD. On December 17, 2010, the Reporting Person gifted shares representing 9.6% of the total shares outstanding of IPFD to the Trust. The transaction was done for estate planning purposes. The Reporting Person disclaims beneficial ownership of the IPG common stock held by IPFD, except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of the beneficial ownership of all the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. Angelo P. Lopresti, Attorney-in-fact 2010-12-21