Shares of Janus Capital ( JNS) dropped after the Denver-based mutual fund company set a $500 million stock buyback. The plan adds to $124 million available under a previous plan. The board also approved a majority-vote standard for the election of directors in uncontested elections. Shares slipped 22 cents, or 1%, to $21.07. Marshall & Ilsley ( MI) said CFO John Presley has resigned to take a strategy job at Fifth Third ( FITB). The Milwaukee-based bank said it has started a search for Presley's successor. Shares dipped a penny to $43.14. Public Storage ( PSA) slipped after the Glendale, Calif.-based real estate investment trust agreed to acquire Shurgard ( SHU), a Seattle-based REIT. Shares of Public Storage slipped $1.64, or 2%, to $77.82. GFI Group ( GFIG) fell after the New York-based brokerage posted a sharp rise in fourth-quarter earnings. The company made $11.4 million, or 40 cents a share, compared with $3.4 million, or 14 cents a share, a year ago. The company earned 45 cents a share excluding one-time items. Analysts were looking for the company to earn 43 cents a share. Revenue increased 33% to $140.3 million. The company also said it plans to file in the second quarter for a secondary offering of roughly 3.5 million shares held by GFI shareholders. Shares slipped $3.79, or 7%, to $50.91.