One of David Einhorn's Greenlight Capital hedge funds has gotten off to a terrible start to 2018

Reuters

Greenlight Capital founder David Einhorn at the Sohn Investment Conference in New York City, May 8th, 2017

• The Greenlight Capital (Gold) fund fell 6% in January, while the S&P 500 rose 4.75%.
• It extends a tough streak for David Einhorn's hedge fund.

David Einhorn's Greenlight Capital is having a rough start to the year.

The Greenlight Capital (Gold), L.P. - Dollar fund fell 6% in January, according to a January 31 client update seen by Business Insider. By comparison, the S&P 500 rose 4.75% in January.

According to a regulatory filing, the fund has "have an investment strategy that is substantially the same" as the firm's flagship strategy.

In the client update, Greenlight said most of the losses occurred in the last week of January:

"Given our poor January result, we wanted to provide some context. Our long portfolio only achieved about half the S&P 500 return, while our short portfolio went up more than twice the index. The underperformance was broad-based with many shorts rising 15% or more and no significant longs performing at that level. Most of the losses occurred in the last week of the month. We are managing the portfolio prudently, including single stock and long and short exposures. We believe the valuation spread between our longs and shorts is as wide as we can remember. "

The fund was about 123% long and 73% short, according to the update.

Greenlight has been struggling recently.

The firm's flagship fund returned 1.6% last year after fees, compared to a 21.8% gain in the S&P 500, Business Insider previously reported.

Greenlight lost 1.6% in the fourth quarter last year, compared to a 6.6% gain in the S&P 500 over the same period.

In a January 16 client letter, Greenlight said it was frustrated by the underperformance.

"As we were in the batter's box so to speak, it felt like we were swinging well and hitting the ball hard," Greenlight said. "We just didn't deliver a satisfactory result on the scoreboard."

A spokesman for Greenlight declined to comment.