By Svea Herbst-Bayliss

NEW YORK (Reuters) -Proxy advisory firms Institutional Shareholder Services and Glass Lewis on Monday recommended that shareholders reject Ritchie Brothers Auctioneers Inc’s planned $7 billion acquisition of U.S. auto retailer IAA Inc.

As investors often follow recommendations from the proxy firms, the move deals a blow to one of the year’s most widely watched takeover deals, which was first announced in November.

Both advisors underscored the potential risks associated with the deal, with ISS pointing to a drop in the stock price after the transaction was announced and a lag in performance as reasons for concern.

“It appears that RBA’s strong standalone prospects, proven over a period of time through robust performance, offer a better understood and verified path to shareholder value creation,” ISS wrote in its report, which was seen by Reuters.

Shareholders vote on March 14 on whether to approve the proposed deal.

Ritchie Bros. said it “strongly disagree(s)” with the recommendations and urged shareholders to support the deal.

The Ritchie Bros. stock price was up nearly 3% in early afternoon trading on Monday. IAA’s stock price dropped nearly 7%.

“The IAA transaction is expected to unlock substantial additional value that neither Ritchie Bros. nor IAA could achieve on its own, and we are confident in our ability to realize it,” Ritchie Bros. said in a statement.

The statement also said Ritchie Bros. is committed to act in the best interest of all Ritchie Bros. shareholders and build long-term value and drive superior shareholder returns.

“We continue to believe that combining Ritchie Bros.’ and IAA’s marketplace capabilities will create a unique value proposition with significantly increased earnings power and stockholder value creation relative to either company’s standalone prospects,” IAA said in a statement.

For Ritchie Bros., a Canadian company that auctions and sells used heavy industrial equipment, the acquisition is intended to diversify its customer base, boost growth and strategic plans by giving it a bigger footprint in vehicle re-marketing, and help cut costs.

In January, Ritchie Bros. received a $500 million investment from activist investor Starboard Value that allowed it to revise the deal terms and win critical support from investor Ancora Group Holdings, which had previously opposed the deal.

But a number of investors on both sides are pushing back, arguing it would distract Ritchie Bros. from its core business and that it favors IAA shareholders without offering enough upside for RBA investors.

Luxor Capital, which owns roughly 4.2% of Ritchie Bros. and has been urging other shareholders to vote against the deal, welcomed the recommendations. “ISS and Glass Lewis agree that a standalone Ritchie Bros. will drive more value for shareholders, with less risk, than a merger with IAA’s second-tier business,” Luxor president Doug Snyder said in a statement.

(Reporting by Svea Herbst-Bayliss and Kannaki Deka in Bengaluru; Editing by Chizu Nomiyama, Jan Harvey, Tomasz Janowski and Sherry Jacob-Phillips)

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