(Adds details on Kretinsky's investments, background on VESA, updates shares)
   Sept 17 (Reuters) - Czech billionaire investor Daniel Kretinsky's VESA Equity Investment became the fourth largest stakeholder of Sainsbury's , owning a 3.05% stake in the British supermarket group, according to a filing on Thursday.
   Shares of Sainsbury's, which touched a session high of 191.25 pence in response to the disclosure, were up 3.1% at 190.9 pence at 1314 GMT.
   Kretinsky, who forged one of Europe's largest energy groups through more than a decade of deals, has been diversifying and scouring retail, media and other areas for investments. 
   The Czech billionaire, which owns the biggest stake in Royal Mail through VESA Equity, has increased its investment in the postal company over the past few months, from around 4% in April to 13.1% as of July.
   Another vehicle owned by Kretinsky, EP Global Commerce, is also a major shareholder in German wholesaler Metro . 
   VESA Equity's portfolio also includes stakes in U.S. retailer Foot Locker Inc and department store chain Macy's Inc , data from Refinitiv Eikon showed.

(Reporting by Yadarisa Shabong in Bengaluru; Editing by
Shinjini Ganguli)
((Yadarisa.Shabong@thomsonreuters.com; Twitter:
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