Twitter is paying approximately $350 million in stock to acquire MoPub, a San Francisco-based mobile app monetization company. MoPub had raised just over $18 million in VC funding from Accel Partners, Harrison Metal Capital, Iris Capital and Jafco Ventures. www.mopub.com

Kemira Oyj (Helsinki: KRA1V) is seeking a buyer for its formic acid unit, according to Bloomberg. The deal could be valued at around €200 million, with private equity firms and Germany’s Addcon Group reported to have expressed interest. www.kemira.com

Koch Industries has offered to acquire Molex (Nasdaq: MOLX), a Lisle, Ill.-based maker of electronic components like electronic plugs for Apple products, for $7.2 billion. The $38.50 per share bid represents a 31% premium to last Friday’s closing price for Molex common stock and a 56% premium to its Class A shares. www.molex.com

Marathon Oil Co. (NYSE: MRO) has agreed to sell its stake in an oil and gas field offshore of Angola for $590 million, to Angola state-run company Sonangol EP. www.marathonoil.com

Time Inc. has agreed to acquire the five titles of American Express Publishing Magazine Group – including Food & Wine and Travel & Leisure – for an undisclosed amount, according to the NY Post. Time Inc. has had a strategic back-office agreement with Amex Publishing for decades, and reportedly had first dibs on the assets were they to go on the block. [Note: Term Sheet and Fortune are published by Time Inc.]

Endurance International Group Holdings, a Burlington, Mass.-based provider of cloud solutions for small and mid-sized businesses, has filed for a $400 million IPO. It plans to trade on the Nasdaq under ticker symbol EIGI, with Goldman Sachs, Credit Suisse and Morgan Stanley serving as lead underwriters. The company reports a $65 million net loss on $251 million in revenue for the first six months of 2013, compared to a $39 million net loss on $92 million in revenue for the year-earlier period. Shareholders include Warburg Pincus and Goldman Sachs. www.enduranceinternational.com

Geopark Ltd., a Santiago, Chile-based oil and gas exploration and productions company, has filed for a $100 million IPO. It plans to trade on the NYSE under ticker symbol GPRK, with J.P. Morgan, BTG Pactual and Itau BBA serving as lead underwriters. The company’s stock currently trades on both London’s AIM and the Santiago Offshore Stock Exchange. www.geo-park.com

Aramark, a Philadelphia-based concessions company, has filed for a $100 million IPO. It plans to trade on the NYSE, with Goldman Sachs listed as left lead underwriter (15 banks listed in total). The company reports $107 million in net income on $13.5 billion in revenue for its fiscal 2012, compared to $85 million in net income on $13.1 billion in revenue for its fiscal 2011. Aramark was acquired for $6.3 billion in 2006 by Warburg Pincus (21.5% pre-IPO stake), Thomas H. Lee Partners (21.05%), GS Capital Partners (21.05%) and CCMP/JPMorgan Partners (21.04%). www.aramark.com

Ophthotech Corp., a Princeton, N.J.-based developer of therapies for wet and dry age-related macular degeneration, has set its IPO terms to 5.72 million shares being offered at between $16 and $19 per share. It would have an initial market cap of approximately $494 million, were it to price in the middle of its range. The company plans to trade on the Nasdaq under ticker symbol OPHT, with Morgan Stanley and J.P. Morgan serving as lead underwriters. It has raised more than $200 million in VC funding, from firms like Novo AS (28.65% pre-IPO stake), SV Life Sciences (26.8%), HBM Healthcare Investments (15.21%) and Clarus Ventures (13.57%). www.ophthotech.com

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