Well said Moose.Fishy, you're on target.
If you're a decent consultant, then there are likely other jobs down the road. If not, there's another line of work or another way to get by.
Whether publicly traded or not, harassment at the work-place is illegal.
I tend to use the word snitching where victimless or consensual crimes are involved. When it involves others being victimized, it's not snitching, it's taking a stand and making it right.
As another person mentioned, or implied, you need to have some corroboration with the women being harassed. If you stand up, and they deny anything happened, then -you're- out on a limb, looking like a nut-case.
If you have a decent work relationship with any of the women being harassed, talk with them, and let them know it bothers you. See where they're at with you drawing attention to the issue. See if they'd speak with someone not associated with the job.
If nothing else, let the fellow know that he's about to screw up a meaningful gig, and he's preparing to toss it all away because he can't keep his hormones or his pecker under control.
Good luck. But it's YOUR face you'll be looking at in the mirror every day for the rest of your life.
Gather as much info as you can. Document, document, document. Every little thing you see and hear, right it down and time stamp it. Better yet, record it if possible.
Something else you might encourage is if you show these women being harassed that you support them, it may embolden them to tell the guy off. They might be able to modify his behavior by being confrontational when he does it. And once one woman does, it will hopefully encourage others to do it as well.
And don't ever try to "White Knight" a situation unless it gets out of hand. If it's one thing I've learned over the years, women do not want someone to handle their problems for them. They want support and advice, but ultimately want the action to be theirs.
Of course if the universe were just, someone like my sister would get hired and she'd handle the situation poste haste. Several years ago she had a guy grab her boob at work. So she broke his nose. She got a talking to and he got fired.