WASHINGTON, June 9 (Reuters) - The Senate Health, Education, Labor and Pensions Committee unveiled proposed legislation to overhaul the U.S. insurance market and expand coverage to millions of uninsured Americans.

The panel is one of two in the Senate working on a healthcare overhaul that President Barack Obama hopes to sign into law by October. Three committees in the House of Representatives are working on similar legislation. Here is a summary of the Senate proposal.

INSURANCE MARKET REFORMS

* A new public insurance plan would be created, but the bill at this point leaves open details of how it would be designed.

* Individuals would be required to obtain insurance, the proposed bill leaves open details on whether employers should be required to provide coverage to workers.

* Insurance companies would be barred from refusing to cover people or charging them more because of health history or gender.

* Insurers also would be required to cover some preventive services.

* Annual or lifetime limits on coverage would be prohibited.

* Children would be allowed to stay on parents' insurance plan up to age 26.