Surreptitious online measures can reveal processing of stimuli that people did not report noticing or could not describe. People seem to glean everything from low-level Gestalt grouping information to semantic meaning from unattended and unreported stimuli, and this information seems capable of influencing performance and priming semantic judgments. Moore and Egeth (1997) provided evidence that judgements about the lengths of two lines were influenced by the grouping of background dots, even when subjects did not notice the pattern they formed. Mack and Rock (1998) reported that subjects could be primed to complete a stem with a word to which they were inattentionally blind. In this registered report, we replicated these two classic findings using large online samples (Ns=260 and 448), finding support for the influence of grouping despite inattentional blindness but not for word-stem priming.