How do I stop LinkedIn from inviting my friends over and over again?

Question From User - Answers in Comments.

I used my Outlook address book to send a connection invite to LinkedIn.

Problem is....after I connected with those that chose to connect/sign-up....the rest of them continue to get repeated "invites" over and over again every few days.

A friend showed me the invite...and apparently there is no "opt-out" for these people.

Is there a way I can stop these people from getting continued invites after the fact?

Thanks!