While many investors moved to the sidelines in August and September, the market slide was no deterrent to officers and directors at many companies. Insider-buying was robust throughout the period and continues at high levels now that earnings season is underway (at which time “buying windows” open up for insiders).

I’ve been running through all of the insider transactions, focusing on companies that saw a cluster of buying after shares fell in the summer market rout. Of all the stocks reviewed, these three look most appealing.

#-ad_banner-#1. Avis Budget (NYSE: CAR) 
Talk about a lost year. Executives at Avis Budget and Hertz (NYSE: HTZ) spent much of the last year entangled in a bidding war to acquire Dollar Thrifty (NYSE: DTG). The proposed purchase prices climbed ever higher, quickly sapping any accretive possibilities for the winner, so it’s perhaps best that no deal was ultimately consummated. Nevertheless, the damage was done. Shares of Avis Budget had soared to almost $20 on hopes that all industry players would benefit from any deal that reduces competition. Now, the stock is back at $12, right where it was a year ago.

Yet Avis still has arrows in its quiver. A $1 billion deal to re-acquire its European franchise should boost profits. The combined entity will have more than $7 billion in annual revenue, and the deal should bring about $30 million in synergies. More importantly, the deal helps the company compete for global contracts with multinational firms that had to stick with Hertz if they were to work with one vendor in the United States and Europe.

A recent quarterly snapshot shows Avis Budget is healthy and getting healthier. Third-quarter EBITDA will be above $250 million, according to an early-September pre-announcement. A year from now, all other things being equal, this figure should exceed $300 million when results from Avis Europe are incorporated. EBITDA gains are coming from the fact that used-car prices are very strong, meaning car-rental agencies can recoup more of their investments as they turn over their fleets. Meanwhile, the entire company’s equity is valued at just $1.26 billion, and coupled with the debt, comes in under $4 billion.

With $600 million to $800 million in potential annual EBITDA generation, shares look quite oversold, which is the likely reason behind heavy insider-buying. A total of 15 insiders bought a little more than 100,000 shares — collectively — in early October.

2. Ligand Pharma (Nasdaq: LGND)
Ligand’s insiders have been “buying in the way up,” meaning they’ve continued to accumulate shares even as the stock’s price has risen. The buying began in early August when BVF Partners (which owns more than 10% of the company and, for our purposes, is defined as an insider because the large investor can’t trade on material non-public information and must file every time shares are bought or sold) bought 600,000 shares over a three day period, worth about $10 million, at just under $11 a share. Since then, several company directors have also been buying at prices as high as $15. Shares are back down to $14 currently, and look to have solid upside from here.

This is a unique biotech company. Rather than develop its own drugs, Ligand invests in other biotech firms, generating income from milestone payments and royalties that small firms get from their Big Pharma partners. Ligand likes to focus on early-stage firms needing cash and possessing considerable upside. Right now, Ligand has a hand in more than 50 companies, about half of which have already pushed their drugs to Phase II clinical trials or beyond.

To get a sense of the value of Ligand’s investments, you have to do a sum-of-the-parts analysis. Investment banking firm McNicoll, Lewis and Vlak figures shares are a double from here, or worth $30, while I have read elsewhere that a valuation analysis pegs the stock at around $21.

3. Exco Resources (NYSE: XCO)
As I’ve been discussing in recent days, major investors are paying hefty prices to snap up natural-gas–producing properties.

While I’ve been looking at what other companies might prove attractive in an M&A scenario, I can’t help notice that mega-investor Wilbur Ross is setting his sights on this oil and gas firm, which operates more than 7,000 wells in Texas, Louisiana and Appalachia. By early August, Ross’ stock purchases pushed his ownership position to about $12 million, or more than 10% of the company. Since then, he’s bought more than 1 million more shares — most recently on Oct. 13 — though he has an agreement with the company’s board that his ownership stake won’t exceed 20% — at least as part of any hostile takeover.

Ross has been angling to profit from Exco for quite some time. He was part of an ownership group that initially sought to buy the company in 2010 for $4.36 billion ($20.50 a share), an offer that was eventually deemed to be inadequate by the company’s board. The stock has subsequently swooned, and the company is now valued at just $2.5 billion.

Ross is taking advantage of the dip, but likely still eyes some sort of exit strategy for the company at a presumably higher price. The last deal fell through in part because the board was concerned that the acquiring consortium would be too debt-constrained to fully exploit the company’s massive shale acreage. Ross, with plenty of financial firepower on his own, would likely be able to prove to the board that he can bring a stronger financing base. Could another $20 a share buyout offer be in the works? Might the board re-consider its openness to such a move, now that shares are just above $10? Time will tell.

Risks to Consider: Insiders have a clear read on their businesses, but they are notoriously bad market timers, and often buy a company’s stock before it has finally hit bottom. Their insider buying signals should be just one part of your research process.

Action to Take –> These insider purchases are major commitments from officers and directors that already own a significant amount of company stock. Their decision to boost their holdings even further is a sure sign of company-specific bullishness, even if the broader market faces stiff headwinds. Each of these three stocks appears to be good deals right now, though you should research these names further before committing to buy.