I’ve been attending the Kleiner Perkins gender discrimination trial for the past week looking for irrefutable examples of gender discrimination, but so far I haven’t seen the bombshell disclosures that would lead me to think Kleiner is sunk.

And that’s even though the firm lost a key ruling Thursday on whether it could introduce evidence of Ellen Pao’s financial woes into the case to argue that she was motivated in part by money to file her lawsuit.

After talking to experts on the issue of gender and bias, the lack of a smoking gun is not surprising. Instead, these cases are tough to prove because they are often filled with small, everyday examples from the workplace. There is the dismissive tone in emails, the bawdy chitchat in breakrooms, the office layout with the power corridor, and seating charts at conferences.

This case is no exception. Much of the trial has been taken up with office atmospherics and what they might have meant. Who sits where at a meeting. Who is invited to dinner with the clients during a work trip. Who is asked to take notes at a meeting. Who is copied in an email, or left off entirely.

Take one of the most notorious examples: a dinner with Al Gore that included only male Kleiner employees. Was it part of a general pattern of excluding women from important work events — Pao lived in the same building as the former vice president, she noted — or simply because Gore’s apartment was small, as the event organizer said? Certainly it was regrettable. All-male dinners and ski trips were a missed opportunity for women to forge alliances that are so critical at this sort of partnership.

There were some clearer-cut examples of boorish behavior, of course, like the conversation about porn stars between male partners and a firm’s client, with Pao on the periphery.

But then there were murkier examples, like the “weird” gift Pao received from a partner, a book with sexual imagery and language. She didn’t complain to the firm’s leaders about it, and Kleiner’s lawyer argued it was a simple gift given to Pao after she gave the partner a gift.

“Standing alone, the examples don’t seem that significant,” said Jason Knott, a litigator with Zuckerman Spaeder in Washington, D.C., who focuses on business and employment disputes. “But when you stand back, it can look discriminatory.”

I thought testimony about the employee review process produced some of the most interesting detail about the small, subtle stuff of gender bias. Pao was told she was too timid and not commanding enough. But she also had her knuckles rapped for being seen by co-workers as shrill, abrasive and not nurturing of others. Male co-workers were praised for traits that did not sound all that different.

“The micro indignities can really erode a person’s sense of comfort in the workplace,” said Jennifer Chatman, a professor of management at UC Berkeley. “They can interfere with a person’s performance. You are getting a window into that in this trial.”

The Kleiner trial comes at a time when gender has become one of the valley’s hot-button issues.

At the trial, Pao, a former junior partner at the firm, certainly tried to make the case about more than herself.

“There should be equal opportunity for women and men to be venture capitalists,” she said, raising her voice from the stand. “I think it’s important, as a person who wanted to be a venture capitalist, but wasn’t able, to make those opportunities available in the future.”

By saying this, she linked her struggle to those of other women in tech who have experienced limited opportunities, sexual advances and oddball statements in the workplace and wondered if their gender, somehow, made a subtle but detrimental difference in their own careers.

“There is a vague feeling that Silicon Valley is a white boys club,” said Steven Tindall, a partner at Rukin Hyland Doria & Tindall in San Francisco, who specializes in employment and class-action litigation. “Will this case be the standard-bearer for gender discrimination in the industry?”

And there have been efforts among tech companies to address what’s indisputable — that there are too few women in tech. From Sheryl Sandberg’s “Lean In” to unconscious-bias training at places like Google, some tech leaders have begun looking inward to find ways to truly level the playing field.

These are baby steps, but at least they are steps.

For Pao to win her case, the jury has the tough job of deciding whether, but for her gender, she would have succeeded at Kleiner.

That may be too hard to determine. But Pao deserves some credit for taking on Kleiner and shining a spotlight on how women and men may experience the workplace differently, and I think tech companies would be smart to take notice and ask themselves: Is this happening here?

Contact Michelle Quinn at 510-394-4196 and mquinn@mercurynews.com. Follow her at Twitter.com/michellequinn.