Laszlo Bock, Google’s SVP of People Operations, heads up the talent at the world’s most attractive employers, and so he’s seen a lot of resumes – more than 20,000 according to a recent post Bock wrote for Linkedin about the biggest mistakes he sees on resumes. So, it’s probably safe to say that he’s a good guy to be doling out advice.

As such I thought I’d share the mistakes listed in Bock’s post, lest you be making them. See, the weird thing about these resume mistakes is that people apparently keep making them, over and over again. It seems that, given how much information there is out there about how to craft a killer resume and cover letter, this wouldn’t happen. But things are never what they seem, I guess. And, as Bock points out, any one of these all too common errors can eliminate you from the running, even if you’re otherwise a good candidate. So, be careful. Don’t get rejected on a technicality.

Here are Bock’s top five resume mistakes.

Typos. This one might seem obvious but people make typos all the time. A 2013 CareerBuilder survey reportedly found that 58% of resumes – more than half! – have typos. The thing about resumes is that we’re always tweaking them, and the more edits we make, the more likely we are to mess something up.

To correct, Bock advises you to proofread your resume and have someone else do it for you as well. I would add, make that two or three other people.

Length (too much of it). Bock suggests that a good rule is one page of resume for every ten years of work experience and states the simple truth that a 3 or 4 page resume won’t get read, no matter how great you are. That might get harder to fit in as job hopping increases – 51% of people now stay in a job for less than two years on average – but it will be a good lesson in writing well and learning to highlight what matters. You don’t have to have your entire history in there, just the parts that will really make someone say “Wow! Let’s bring this person in for an interview.”

Formatting. Keep it clean. Bock says, “Unless you’re applying for a job such as a designer or artist, your focus should be on making your resume clean and legible. At least ten point font. At least half-inch margins. White paper, black ink. Consistent spacing between lines, columns aligned, your name and contact information on every page.” Make sure it can be opened in a variety of formats. You’d hate to miss out on a job because your resume is in Pages and the hiring manager can’t open it on a PC. PDF is a good option.

Confidential information. This one I had actually never thought of. Sharing confidential company information about your current employer with a potential new employer is a screaming red flag. Bock points to a resume from a candidate working at a company with a strict confidentiality policy that stated “Consulted to a major software company in Redmond, Washington.” The candidate, who thought he was being clever, didn’t have to name Microsoft for Bock to know what he was talking about. Why would a new employer trust anyone who would betray a previous employer that way? No smart one would. Bock estimates that “at least 5-10% of resumes reveal confidential information.” I didn’t know that. Don’t be a jerk. You know when you’re being one even if you don’t admit it. Just don’t do it.

Lies. Bock writes, “People lie about their degrees, GPAs, and where they went to school. People lie about how long they were at companies, how big their teams were, and their sales results, always goofing in their favor.”

OK, yes, Bock is right, you should not lie. It’s really easy to get caught and even if you’re not caught and do get the job, if the lie comes out later, even years later, you’ll probably lose whatever job you have at the time.

It’s worth noting, however, that one study by Backgroundchecks.org found that only 51% of employers will dismiss you outright because of a lie, while 40% say it would depend on what the lie was about, and 7% said they’d be willing to overlook a lie if they liked the candidate. But I’m not endorsing lying, just reporting that facts. Don’t lie. Lying is bad.

So, those are Bock’s top resume mistakes. Don’t make them, particularly if you’re applying for a job at Google.

See his post here.