While many companies' shares are rising past their fair values now, others are trading at potentially bargain prices. The difficulty with bargain shopping, though, is that you may be understandably hesitant to buy stocks wallowing near their 52-week lows. In an effort to separate the rebound candidates from the laggards, it makes sense to start by determining whether the market has overreacted to a company's bad news.

Here's a look at three fallen angels trading near their 52-week lows that could be worth buying.

Value these juicy margins

Although it's appeared on this regular series before, I'd strongly suggest value stock investors consider giving biotechnology giant Gilead Sciences (GILD 0.10%) a closer look following its first-quarter earnings "flop."

For the quarter, Gilead Sciences announced $7.68 billion in net product sales, up modestly from the $7.41 billion reported in the year-ago period. More important, though, sales of once-daily hepatitis C pill Harvoni, which treats the most common type of HCV (genotype 1), fell 14% to $3.01 billion from Q1 2015. Many investors viewed this slowdown as worrisome and sold off Gilead Sciences' stock on the news. As for me, I view the drop as renewed reason to consider this cash flow giant an attractive investment opportunity.

Image source: Flickr user NIH Image Gallery.

To begin with, it's not as if Gilead Sciences competitors are really eating into its HCV dominance (which sits around 90% market share). Merck launched its once-daily HCV pill Zepatier following its Food and Drug Administration approval in late January, but it only managed to wrangle $50 million in first-quarter sales, which is hardly worrisome for Gilead. By a similar token, AbbVie reported $414 million in global Viekira Pak sales, but actually saw a 9% decline in U.S. sales. It simply appears that Gilead hit the low-hanging fruit in terms of HCV patients over the past year and is settling into a healthy and predictable demand range for Harvoni.

Gilead Sciences also has an exceptionally deep pipeline of potential blockbusters. In April, Gilead's latest HIV therapy, Descovy, was approved in early April by the Food and Drug Administration and offers patients a considerably more effective and safer tenofovir-based medication. Peak annual sales of Descovy are expected to approach $2 billion. Gilead is also working on a pan-genotypic HCV treatment that could be approved late next month, and it's researching other drugs as possible treatments for hepatitis B and nonalcoholic steatohepatitis.

Gilead offers one of the highest profit margins of all publicly traded companies (55%), but is currently valued at a minuscule seven times forward earnings. With free cash flow likely approaching $20 billion annually, Gilead is a company that should be on value investors' radars.

Nothing could be finer

For value investors, nothing may be finer than owning a refiner like Valero Energy (VLO -1.45%).

Valero Energy has come well off of its highs set during the fourth quarter of last year as a number of year-over-year comparisons have starting working against its bottom line. Within the company's refining segment, adjusted operating income fell roughly $900 million since Q1 2015, which Valero attributed to weaker distillate margins, "narrower crude oil discounts relative to the Brent benchmark," reduced fuel oil profit margins, and of course a warmer-than-expected winter. With margins shrinking, investors have begun to head for the exit.

Image source: Valero Energy.

But value investors who are looking for strong cash flow and a business that's vital to U.S. economic growth would be wise to dig deeper into Valero Energy.

Arguably, the best reason to buy and hold a company like Valero is the intermediate outlook in the oil industry. The dynamics within the oil industry have shifted dramatically now that crude prices have tumbled by more than 60%. Supply and demand equilibriums aren't simply going to reset overnight, meaning there's a strong likelihood of crude prices remaining at depressed levels (relative to 2013-2014) for years to come. Refiners love depressed energy prices, because it boosts demand for gasoline, fuel oil, and other petroleum-based products. Even if margins fall a bit, a big uptick in demand can ensure refiners remain healthfully profitable.

Valero's willingness to expand its own operations may also translate into rapid growth. Valero recently opened a $360 million crude refining facility in Corpus Christi, Texas, capable of refining 70,000 barrels per day, and a $400 million crude refining unit in Houston capable of 90,000 barrels per day is on track to start up beginning in the second quarter. Both crude topping units should give Valero more access to run lighter crudes. 

Having already returned $547 million to investors via dividends and share buybacks during Q1, and trading at just eight times next year's profit projections, Valero looks to be a cheap company value investors should consider buying.

A value stock that could run higher

Lastly, if you're looking for a good deal, it might be time to consider footwear retailing giant Foot Locker (FL 2.08%), which is trading near its 52-week low.

Image source: Foot Locker.

Despite joining the S&P 500 at the end of the first quarter, which typically provides a boost for a company's stock, Foot Locker's valuation has been burning rubber in the other direction. Although no specific fundamental event stands out, the likely reason for Foot Locker's weakness stems from weak U.S. GDP growth in the first quarter of 0.5%. When U.S. economic growth slows, the consumer is liable to holster their spending, which could be bad news for retailers like Foot Locker.

However, if there's a retail segment that can thrive even in a slow-growth environment, it's branded footwear. In the company's fourth-quarter report, released in February, Foot Locker announced record annual revenue of $7.41 billion, a 3.6% increase from the prior-year period. On a comparable-store sales basis, though, sales jumped 8.5% in 2015. For Foot Locker, 2015 marked its fifth straight year of record profits. As long as Foot Locker continues to carry in-demand brands, it can stave off the allure of buying footwear and apparel online.

Adding to the previous point, Foot Locker's tight relationship with Nike (NKE 0.58%) should also boost its long-term business. Nike is one of the most recognizable brands in the world, and it alone can draw consumers into Foot Locker's bricks-and-mortars stores. In its latest quarter, Nike announced constant currency revenue growth of 14% and worldwide futures order growth of 12% from the previous year. As goes Nike so tends to go Foot Locker.

Assuming innovation keeps Foot Locker in the driver's seat in terms of kids footwear market share, and its expansion efforts into Europe pay dividends, Foot Locker's forward P/E of 12 could prove incredibly inexpensive.