Forensic chemist and forensic document analyst expert Erich Speckin was one of the unknowns working behind the scenes during the Maricopa County Audit to analyze the paper and the ballot files that were used in the 4th largest county in America. During this process, he revealed that at least 36,000 ballots were questionable and should be further examined. Most of these ballots (~25,000) were not printed from the official pdf, which caused anomalous discrepancies on these ballots to make them easily distinguishable from their authentic counterparts.
According to Speckin, the ballots printed from the original pdf would be “perfect”. They would have perfectly straight lines with no breaks, etc. However, when he examined the early and election day ballots, there were approximately 25,000 that had “breaks in all the same places” around the ovals. And they were in the same place on all of the anomalous ballots. You can see Speckin’s video about his work in Maricopa here (about 9 min).
Another anomaly that Speckin found in Maricopa Co dealt with batches that went almost entirely for one candidate. Speckin found 61 batches each containing 200 ballots that were presented that had 0ver 90% of votes cast for a specific candidate. In analyzing these batches, it was determined that 58 of the 61 had votes favoring Joe Biden by 90% or more and only 3 favoring Donald Trump by 90% or more. This would mean that these combined batches went approximately 11,600 Biden to 600 Trump, in a state that has been red for approximately 40 years and in a county that was within 2.2% points of each other.