Question about iMac EFI Firmware Update 1.3

I have an iMac and recently have been asked to download and install iMac EFI Firmware Update 1.3 via Software Update. So I did. And then it asked me to do it again another day. So I did again… But it keeps popping up sporadically asking me to install the update even though I have already done so.

Anyone else run into this? What can I do to make it stop?

Thanks for your help!!!