Yes, you can +1 a link without sharing it, similar to clicking 'like' for Facebook. Your +1s are minimally visible or only visible to you, just like a Facebook

Yes, you can +1 a link without sharing it, similar to clicking 'like' for Facebook. Your +1s are minimally visible or only visible to you, just like a Facebook 'like' is minimally visible in a timeline. Sharing on Google+ creates a more prominent but soft broadcast/recommendation/endorsement to the public or to your friends (via circles). Out of curiosity, I tried two scenarios: +1 button on a website/link = I shared with a circle and it counted as a +1 automatically. This is NOT what Google is doing when you share a search result, so you are not +1'ing that shared-from-the-search-results url. Sharing a link directly through the Google+ UI at plus.google.com = NOT automatically +1'd. This is what Google is doing with the 'share' link in search results. Sharing a search result does not +1 it while it does broadcast it to the circles you choose.