Third-party blocks with a smiling face or an umbrella with 2 dots on each side I bought a bunch of duplos from the thrift store and inside there was not Just duplos but also mega bloks. I was able to separate most of them but there are a few that I just cannot tell which is which. They have a logo in the middle  of the stack but its a picture rather than a word.  I'm trying to find anything online but am having no luck. The logo almost looks like a smiling face or an umbrella with 2 dots on each side.
After some searching, I have finally come up with the brand.

I too purchased a lot of bricks and found these odd ones in the mix, they are Tandem bricks, and there isn't too much information out there on them.