Goldman Sachs added Facebook (FB) and Acuity Brands (AYI) to its Focus List today, calling the social network operator an "asset-light tech disruptor," while seeing the lighting solutions provider as benefiting from the "emerging low carbon economy."

FACEBOOK 'MOAT EXPANDING': Facebook has "a large, sticky user base" that should enable it to gain share in the growing digital ad market, according to Goldman analyst Derek Bingham. Moreover, its "industry leading engagement" should provide it with many opportunities going forward, the analyst stated. However, Facebook investors should monitor the efficacy of the social networking giant's ads, "the privacy and regulatory environment," and the company's "high levels of stock-based competition," wrote Bingham.

ACUITY A 'LOW-CARBON LIGHTING LEADER': Focused on LED lighting solutions, Acuity has the "strongest competitive positioning" in the lighting space as LED-based technologies proliferate, Bingham believes. Since 55% of Acuity's revenue is generated from LED, it has less exposure to older technologies than its peers, according to the analyst. Additionally, its focus on downstream means that it doesn't face the pricing pressure of "commoditized" upstream LED products, said Bingham, who expects Acuity to continue to generate "sector leading margins and returns" going forward.

WHAT'S NOTABLE: In conjunction with the additions, the firm also removed Biogen (BIIB), BorgWarner (BWA), Monsanto (MON), and Grainger (GWW) from its Focus List.

PRICE ACTION: In late morning trading, Facebook fell 1.4% to $128.50 and Acuity gave back 1.8% to $265.83.