If I owned Biogen shares before the merger, what is the new cost-basis for my Biogen Idec shares?
You can determine your new cost-basis by taking the price at the time you purchased your Biogen shares and dividing that by 1.15. For example: • 100 Biogen shares become 115 Biogen Idec shares (100 * 1.15 = 115) • The original purchase price of those Biogen shares was $30.00 • New cost-basis for your Biogen Idec shares is $26.09 ($30 1.15 = $26.09) 10.
