The firm has a $58 price target on the stock, up from its previous $52 price target.
The upgrade comes as BMO feels the company is likely going to acquire some of the Ball/Rexam assets that need to be sold.
U.S.-based beverage package maker Ball Corp. (BLL) is acquiring British peer Rexam in a $6.86 billion deal.
"Silgan is a major player in consumer packaging, has a strong management team, and enjoys stable end markets and margins," BMO said in a note.
"Current valuation is in line with peers', but we believe Silgan us uniquely positioned to benefit from impending regulator-mandated asset disposals from the Ball/Rexam combination," the firm continued.
Shares of Silgan are up by 1.54% to $52.24 at the start of trading on Thursday.
Separately, TheStreet Ratings has a "buy" rating and score of B on Silgan stock. This is driven by a number of strengths, which TheStreet Ratings believes should have a greater impact than any weaknesses, and should give investors a better performance opportunity than most stocks it covers.
The company's strengths can be seen in multiple areas, such as its attractive valuation levels and notable return on equity. TheStreet Ratings feels its strengths outweigh the fact that the company has had generally high debt management risk by most measures that we evaluated.
TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author.