If your 401(k) plan permits loans (if not then amend the plan to permit them for any reason) then each of you can borrow from your accounts up to the lessor of 50% of your account balances or $50,000. If you want to borrow $50,000 from your account but your balance is less than $100,000 then you could rollover your IRA to your 401(k) (assuming your plan accepts rollovers from any source, if not then amend the plan) to increase your account balance. Only funds in your IRA that have never been taxed can be rolled over. If you have any after-tax funds such as nondeductible IRA contributions then these cannot be rolled to the 401(k). Assets in the 401(k) would have to be sold in order to issue you checks for the loans. Once you receive the checks from the 401(k) then you could use the funds to invest in your business. You would need to sign a note for the 401(k), have an amortization schedule for your loan repayments which would have to be repaid on at least a quarterly schedule, and repay the loan over no longer than a 5 year period.