The European Commission has issued a questionnaire seeking views on the Yahoo-Microsoft search deal.
The companies signed a 10-year partnership last year, under which Microsoft will power the search technology for both companies and Yahoo will provide the advertising force.
The deal has yet to be approved by European and US regulators, but the European Commission has said that it will give its final decision on the matter on 19 February.
Reuters has seen the questionnaire and said that it contains 38 questions, including whether the merger will make Microsoft a better competitor to Google.
Rivalling Google is a key aim of the partnership, and European Union anti-trust commissioners realise that the search market needs more competition.
The questionnaire also asks whether the deal will encourage innovation in the search market, according to Reuters.
The EU has only just cleared the Oracle-Sun merger, valued at $7.4bn (£4.5bn), after months of deliberation.
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