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The best advice might be to contact investor relations at General Dynamics. http://investorrelations.gd.com/phoenix.zhtml?c=85778&p=irol-irhome is the web address. They will be able to assist you in transferring the shares into your name (assume that you will need proof of his passing), and also any stock splits
or other adjustments to the share total since purchase. They may also be able to assist in the sale process.
General Dynamics did offer some assistance regarding change in ownership. They use Computershare to track owners, keep these records, and make the transfer you will need to complete before you can sell the shares. From the GD website:
"Who do I contact to replace a stock certificate, notify of a change in address, notify of a transfer in ownership, or obtain an answer to a 1099 question?
If you are a registered shareholder, you can contact Computershare, the company’s common stock
transfer agent and registrar. Computershare maintains the company’s stockholder records and is responsible for disbursing dividend checks.
Attention: Shareholder Relations
PO Box 43069
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