Shareholders in Elan (UNKNOWN:ELN.DL) have seen a bump in the value of their stock following the latest buyout offer from Royalty Pharma. Today, the latter upped its bid for the Irish company to $13 per share, a half-dollar improvement over its most recent bid. Additionally, Royalty Pharma is willing to pay a $2.50-per-share "contingent value right" if Elan's star multiple sclerosis drug Tysabri reaches certain sales goals.

The new offer is still not good enough for Elan's board of directors. In a tersely worded response to it, the company quoted the board as saying simply that its shareholders "are strongly advised to take no action in relation to the Royalty Pharma offer."

Elan stock closed up by nearly 6%, or $0.76, to $13.44 after the offer was made.

Fool contributor Eric Volkman has no position in Elan. Nor does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.