EU mergers and takeovers (March 13)

BRUSSELS, March 13 (Reuters) - The following are mergers under review by the European Commission and a brief guide to the EU merger process:

APPROVALS AND WITHDRAWALS

-- German engineering company Siemens (BSE: SIEMENS.BO - news) to merge assets with Spain's Gamesa to form the world's largest wind turbine maker (approved March 13)

-- Finnish fibre materials company Ahlstrom (LSE: 0DHW.L - news) to merge with Finnish specialty paper maker Munksjo (Swiss: OXMUNK1.SW - news) (approved March 13)

-- Slovenian energy group Petrol to take majority stake in natural gas wholesaler Geoplin (approved March 10)

-- UK tech company Micro Focus to acquire Hewlett-Packard Enterprise's software business (approved March 8)

-- Private equity (IOB: 0QLS.IL - news) firm HIG Capital to acquire IT security products maker Infinigate Holding AG (approved March 7)

NEW LISTINGS

-- U.S. aircraft component maker Rockwell Collins (NYSE: COL - news) to acquire aircraft interior maker B/E Aerospace (notified March 8/deadline April 12)

-- U.S. car part supplier Lear to acquire Grupo Antolin's automotive seating business (notified March 8/deadline April 12/simplified)

-- Private equity firm Partners Group to acquire European operator of clinical pathology laboratory operator Cerba Healthcare from PAI Partners (notified March 7/deadline April 11/simplified)

-- Engie Group French banking group BPCE to acquire a 49.9 percent stake in renewable energy companies LCS 4 and LCS (notified March 3/deadline April 7/simplified)

EXTENSIONS AND OTHER CHANGES

-- Dutch insurer NN Group to acquire Dutch rival Group Delta Lloyd (notified Feb. 22/deadline extended to April 12 from March 29 after the Dutch competition regulator asked to examine the deal)

FIRST (Other OTC: FSTC - news) -STAGE REVIEWS BY DEADLINE

MARCH 16

-- Australian investment bank Macquarie Group (Dusseldorf: 4M4.DU - news) and the UK's National Grid (LSE: NG.L - news) to acquire joint control of National Grid's gas distribution business (notified Feb. 9/deadline March 16)

MARCH 17

-- U.S. wireless carrier AT&T (Sao Paolo: ATTB34.SA - news) to acquire U.S. broadcaster and TV studio Time Warner (Frankfurt: A0RGAY - news) (notified Feb. 10/deadline March 17/simplified)

MARCH 20

-- General Electric Co to acquire rotor blade maker LM Wind Power Holding