In Saudi Arabia, women are not allowed to drive cars and a courageous group of women are trying to fight the ban. The group's use of social media to raise awareness of the injustice not only makes the Saudi government look bad, but has the potential to give car makers a black eye and raise the hackles of socially conscious investors.

That's because the women aren't just limiting the protest to calling on the government to change its ways; today they asked Fuji Heavy Industries Ltd.'s Subaru cars unit to pull out of the kingdom until the prohibition is lifted. Subaru hasn't commented yet. Talk is that the campaign may be extended to Detroit-based General Motors Co.'s Cadillac and Seoul-based Hyundai Motor Co.

U.S. Secretary of State Hillary Clinton has given her support to Saudi Women for Driving, who drove in the country June 17. According to Bloomberg News, the campaign caps a series of developments that began in May, when Saudi women used Facebook  and Twitter to call for females with international driver's licenses to use their cars June 17.

Even if they don't want to pull out of such a lucrative market, global car makers could certainly put some public pressure on the Saudi government to lift the ban rather than looking the other way. And socially conscious investors could also support the efforts of these women by using some shareholder activism to question car makers about what they are doing to end this outright discrimination and potentially increase their own car sales by opening the door for women to drive in Saudi Arabia.

To learn more, visit change.org.