The two companies were now major employers, but both were having problems. McDonnell was primarily a defense contractor, without any significant civilian business. It frequently suffered lean times during downturns in military procurement. Meanwhile, Douglas was strained by the cost of the DC-8 and DC-9. The two companies began to sound each other out about a merger in 1963. Douglas offered bid invitations from December 1966 and accepted that of McDonnell. The two firms were officially merged on April 28, 1967 as the McDonnell Douglas Corporation (MDC). Earlier, McDonnell bought 1.5 million shares of Douglas stock to help its partner meet "immediate financial requirements." The two companies seemed to be a good fit for each other. McDonnell's military contracts provided an instant solution for Douglas' cash flow problems, while the revenue from Douglas' civil contracts would be more than enough for McDonnell to withstand peacetime declines in procurement.