Adds valuation target in paragraph 1 and details throughout

May 26 (Reuters) - Gas engine manufacturer Innio is targeting a valuation of up to $20.25 billion in an initial public offering in the United States, it said on Tuesday.

Munich, Germany-based Innio's principal shareholder AI Alpine - co-owned by funds managed by Advent and ADIA - is seeking up to $2.03 billion in the IPO by offering 75 million shares priced between $24 and $27 per share.

Innio makes gas engines under its Jenbacher and Waukesha brands for a wide array of critical infrastructure, including data centers, microgrids, grid stabilization, industrial energy and gas compression.

Goldman Sachs, J.P. Morgan and Morgan Stanley are joint lead book-running managers for the offering.

Innio will list on the Nasdaq under the symbol "INIO".