Shares of Orbitz Worldwide, Inc. (OWW) are on the slide in Tuesday trading following news that its biggest shareholder has sold about one-third of its position in the online travel agency.  PAR Capital Management unloaded 8.1 million of the 24.6 OWW million shares that it held.  Even with the sale, PAR Capital is still one of the largest Orbitz shareholders and Orbitz remains one of the biggest holdings in PAR Capital’s investment portfolio.

PAR started its position in Orbitz in 2007 (the year Orbitz went public) and added to it late in 2009 as part of a debt-for-equity transaction while the company was employing a turnaround strategy and brought in new management.

“We have tremendous respect for the progress that CEO Barney Harford and his team have achieved and we remain optimistic about the company's future," said Paul Reeder, President of PAR Capital Management. "However, at this juncture, it is prudent for us to liquidate a portion of our investment in order to better diversify our portfolio."

As OWW went public, shares printed highs of $15, but plunged as low as $1.10 as part of the market collapse in 2008/2009. Since, the share value has clawed back near all-time highs, thanks in part to a strong second-quarter earnings report last week that beat Wall Street expectations and an improved outlook for the full year.

On Aug. 8, the Chicago-based company said that revenue rose 12 percent to $225.8 million from $201.0 million the year earlier. Adjusted earnings came in at 17 cents per share, flying past analyst predictions of 9 cents per share on revenue of $218.9 million.

Much like bigger competitor Priceline.com (PCLN) , hotel bookings provided the majority of the lift in overall performance. Room nights grew by 20 percent and revenue from hotels leapt 40 percent.

Looking ahead, Orbitz raised its revenue outlook for the current quarter to the range of $214 million to $220 million, ahead of expectations of $213.8 million. For all of 2013, the company now sees revenue between $840 million and $850 million, again topping analyst calls for $831.4 million.

TripAdvisor, Inc. (TRIP) has also seen shares soar higher in recent weeks with an earnings beat of its own. To that end, the rise in online travel agents seems to have a lot to do with healing economies across the globe, something that could bode well for ongoing appreciation.

Shares of OWW are getting lumped-up with the news the PAR Capital shed a good portion of its holdings, falling 12 percent in Tuesday action at $10.30 each as the day winds towards a close.  Even with the loss of more than $1.40 per share today, shares of OWW are still ahead about 270 percent in 2013.