Mergers & acquisitions

AT&T Inc. (NYSE: T) would consider selling its multi-billion portfolio of Latin American cellphone towers and its 9.6% stake in Brazil-listed phone company América Móvil SAB, according to the WSJ. www.att.com

Avis Budget Group (Nasdaq: CAR) has completed its $500 million acquisition of car-sharing company ZipCar, whose CEO Scott Griffith subsequently resigned. Read more.

Dropbox, a cloud file-sharing company, has acquired the maker of mobile email app Mailbox. No financial terms were disclosed, but TechCrunch reports that the deal was valued at around $100 million in cash and stock. Dropbox has raised over $257 million in VC funding from Index Ventures, Sequoia Capital, Accel Partners, investors Benchmark Capital, Goldman Sachs, Greylock Partners, Institutional Venture Partners, RIT Capital Partners, and Valiant Capital Partners. Mailbox had raised around $5 million from Charles River Ventures, Crunchfund, Kapor Capital and SV Angel. www.dropbox.com

Qatar Holding is not considering a bid for British retailer Marks & Spencer (LSE: MKS), according to Reuters. Marks & Spencer shares had jumped 8% on a Sunday Times report that Quatar Holdings was planning to launch an £8 billion takeover attempt. www.marksandspencer.com

Viko Elektrik, a family-owned Turkish electrical appliances maker, has hired Credit Suisse to find a buyer for around $800 million, according to Reuters.

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