Bombardier Inc. shares jumped the most in a year after a Citigroup analyst said Friday’s 20 per cent drop was excessive because a regulatory review of the company’s executive stock-sale plan “appears routine.”

Bombardier’s Class B stock jumped 23.95 per cent to $2.07 in Toronto on Monday, the biggest increase since last November. Bonds also rose, snapping a six-day decline.

Quebec’s Autorite des Marches Financiers said late Thursday it was reviewing the company’s Automatic Securities Disposition Plan, which executives including Chief Executive Officer Alain Bellemare can use to sell stock. The regulator ordered the suspension of all such transactions until further notice. Bombardier said it would fully cooperate with the probe of the stock-disposition plan, which was adopted in August.

“At this time, there appears to be no reason to believe that the regulator is looking into any alleged improprieties that are related to this program,” Citigroup analyst Stephen Trent said late Sunday in a note. As the investigation “appears routine,” last week’s selloff “looked unreasonable,” he said.

Bombardier shares lost 37 per cent of their value last week -- the biggest decline since at least 1988, according to data compiled by Bloomberg. Bombardier’s US$1.5 billion in bonds due 2025 also led declines among global high-yield notes denominated in U.S. dollars Friday, falling 2.3 cents to 90 cents on the dollar. The bonds rose to 90.75 cents in early trading Monday.

--With assistance from Paula Sambo.