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By Arno Schuetze
FRANKFURT, June 28 (Reuters) - Building materials maker Standard Industries and several private equity groups are vying for BASF's construction chemicals business, which the German chemicals group has put on the block to focus on more profitable operations, people close to the matter said.
Advent, Bain, Cinven, KKR, Lone Star and U.S.-based Standard Industries, which is working in a consortium with Blackstone , are among those who have been chosen to participate in the second round of bidding, they added.
BASF declined to comment. The bidders also declined to comment or had no immediate comment.
The company flagged its intention to auction off or merge the world's largest maker of chemical additives for concrete in October.
One of the sources said that only bidders offering at least 3 billion euros ($3.4 billion) for the unit were invited to enter due diligence and eventually prepare a final offer.
The company's Chief Executive Martin Brudermueller in October set out plans to hive off the unit to boost the group's share price.
The company said at the time that the business, whose products have been used to build train tunnels in the Swiss Alps and in London, was not deeply integrated into BASF's production network and that it had fallen short of profitability targets.
It has grown little since BASF purchased it from Degussa in 2006 for 2.7 billion euros including debt. The unit's business model of catering to a large number of small to mid-size builders goes against BASF's focus on large industrial customers, industry analysts said. ($1 = 0.8785 euros) (Reporting by Arno Schuetze Editing by Paul Carrel and Louise Heavens)