A retirement consulting executive is coming back to Commonwealth Financial Network after a move to LPL Financial lasted all of a month.

Paul Mahan "will pick up right where he left off," Commonwealth CEO Wayne Bloom said in a statement, explaining that Mahan will return to his role as vice president of retirement consulting services. Commonwealth holds the No. 4 spot in Financial Planning's annual FP50 ranking of the biggest independent broker-dealers.

LPL hired Mahan in April as a senior vice president at LPL Retirement Partners, a division it has been beefing up in recent years.

But, apparently, the new situation didn't work out. "I've realized the Commonwealth community is where I thrive, and serve, best," Mahan said in the same statement, which shed no light on the reason for his rapid about-face.

CULTURE CLASH?

Shifting from a high-end boutique operation, with just over 1,487 advisors, to the industry's largest independent broker-dealer, which had almost 13,700 as of year-end 2013, might have proved too big a change, speculates a former LPL executive, who asked to remain anonymous and was not privy to the particulars of the situation.

"I think small, medium and large companies have different cultures," the former executive says. "Some people are just cut out for one, and not another."

Bloom declines to comment on this "big-company theory," but adds, "I can tell you that Paul is a fanatic about quality and our very special community -- and after he left he realized just how much that meant to him."

In his statement, Mahan added, "In my three and a half years with Commonwealth, I had developed incredibly close ties, and I always maintained a great level of pride and excitement in my work -- which I value deeply."

Mahan could not be reached for comment; an LPL spokesman declined to comment.

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