I purchased 2 of these on eBay to install on my supermicro X10 board. No brand name came on them. They were listed as "Intel OEM i350-t4" but suspiciously "intel" appeared nowhere on the board, leading me to believe that they were knock-offs as opposed to officially sanctioned intel OEM boards. If you look closely on the Lenovo or Dell (for example) branded i350-T4 boards, they still come with "intel" silkscreened on the pcb somewhere, normally near the ethernet ports.
Also, the chips on the boards were of a different brand and type than the Dell OEM i350-T4 that I purchased later. The Dell OEM (Dell part: THGMP) had two Delta Electronics "LFE9219C-R" chips, while the generic eBay on had two chips labeled "MR-MACOM" and two different identifying numbers, neither of which yielded any results in a Google search. I did not lift up the heat sink in order to see if there was a difference between the two boards in what lay underneath.
The two boards worked ok in their role of light hyper-v service for about 2 weeks, then they started having issues in Windows Server 2012 R2. The boards started dropping in an out in their connections to my HP 1810-24G v2 switch. Then, Windows device manager started reporting "code 10" and "code 43" errors from the cards and dropping them offline. If I tried to uninstall or re-enable the cards after this, Windows device manager would hang, necessitating a reboot of the server. Different machines and different pcie ports would produce the same error. The supermicro x10 board's pcie ports worked just fine with other cards, leading me to determine that the generic i350-T4 cards themselves were at fault.
I returned the cards for refund for not working and for being possible counterfeit intel i350-T4 boards.