Check out the companies making headlines after the bell:

Shares of Salesforce.com fell more than 3 percent in extended trading Monday after issuing weak first-quarter revenue guidance. The software company released better-than-expected fourth-quarter earnings, posting earnings per share of 70 cents on revenues of $3.60 billion. Wall Street expected earnings per share of 55 cents on revenues of $3.56 billion.

Salesforce.com estimated first-quarter revenues between $3.67 and $3.68 billion, missing expectations of $3.70 billion. The company predicts earnings per share between 60 and 61 cents, lower than the 63 cents forecast by analysts.

GameStop shares jumped about 4 percent after hours Monday after the company announced its board of directors approved a new $300 million share repurchase program. This stock buyback program will be replacing the previous repurchase authorization, which has $170 million remaining. The board also declared a quarterly cash dividend of 38 cents per common share.

Invitae shares plummeted more than 5 percent after hours following an announcement that the genetic testing company started a public offering of $125 million of shares of its common stock. Invitae will also give new shareholders a 30-day option to purchase up to an additional $18.75 million of shares.

Shares of Ascendis Pharma dipped 2 percent after market close Monday after the Denmark-based bio-pharmaceutical company announced it has started a public offering of $400 million of American shares. Buyers will have a 30-day period where they maintain the option to buy an additional $60 million of shares.