X0306 4 2017-06-21 false 0000051143 INTERNATIONAL BUSINESS MACHINES CORP IBM 0001695828 Del Bene Robert F IBM CORPORATION ONE NEW ORCHARD ROAD ARMONK NY 10504 false true false false VP, Controller Common Stock 2017-06-21 5 G false E 4.218 0.00 D 0.00 I Spouse Common Stock 2017-06-21 5 G false E 4.218 0.00 A 8960.324 D Phantom Stock Unit 0.00 2017-08-08 4 A false 55.00 0.00 A Common Stock 55.00 5263.00 D The reporting person disclaims beneficial ownership of the securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. Phantom stock units convert to the cash value of the company's common stock on a one-for-one basis. Acquisition of phantom stock units under the IBM Excess 401(k) Plus Plan. Distribution of phantom stock units under the IBM Excess 401(k) Plus Plan is deferred until separation from the company. The reporting person may transfer these phantom stock units into an alternative investment account under such plan. A. Gomes da Silva on behalf of R. F. Del Bene 2017-08-09