Anti-backout latch for fiber optic connector

An optical fiber connector (14) is provided, of a type that has a housing (70) and a fiber block (72) slideable between forward and rearward positions within a passage of the housing, the housing having guide-receiving spaces (120, 122) on opposite sides of the passage for receiving guides (60) of a mating connector device, which assures that the block will remain in its forward position prior to mating of the connector with the connector device. A sheet metal retainer (110) for retaining the fiber block in the forward position, includes a latch (112) that lies in the path of rearward movement of a shoulder (118) on the fiber block as the fiber block moves rearwardly from its forward position, to resist such movement with a force of a plurality of pounds. The retainer has lifters (130, 132) that project into the guide-receiving spaces, so as the guides move rearwardly along the spaces they lift the lifters which lift the latch to facilitate rearward movement of the fiber block during mating of the connector and connector device.