SYDNEY, Aug 27 (Reuters) - Two bidding groups led by

Blackstone and IFM Investors lodged final offers on Tuesday to

buy Australian data centre group AirTrunk in a transaction worth

about A$20 billion ($13.55 billion), according to two sources

with direct knowledge of the matter.

Binding bids were due on Tuesday and AirTrunk, alongside its

advisers Macquarie and Goldman Sachs, is now examining the

offers, the sources said. There is no deadline for selecting a

winning bid, one of the sources added.

Blackstone bid for AirTrunk alongside consortium partner the

Canada Pension Plan Investment Board (CPPIB), one source said.

The IFM led consortium consists of Digital Bridge, GIP,

Mubadala's MGX and Silver Lake, the second person and a third

source added.

The sources could not be named discussing confidential

information.

Blackstone and CPPIB declined to comment. AirTrunk, IFM, MGX

and Silver Lake did not immediately respond to requests for

comment.

Digital Bridge and GIP declined to comment.

AirTrunk's shareholders led by Macquarie Asset Management

and Canada's Public Sector Pension Investment Board (PSP)

declined to comment.

Macquarie and PSP own 88% of the data centre business but

have not disclosed their individual stakes.

($1 = 1.4760 Australian dollars)