Department of Defense Spare Parts Procurement Improvement Act of 1984

Department of Defense Spare Parts Procurement Improvement Act of 1984 - Requires a defense agency procuring property which will need replacing at a future date to purchase unlimited rights to the technical data relating to such property unless it would be economically disadvantageous to the United States. Requires that such data be available and delivered to the agency within a specified time. Directs a contractor to make available or deliver to the agency all subsequent design changes and revisions in such data. Requires the contractor to certify the data's accuracy and to cure any deficiencies. Suspends progress payments under a contract when the contractor fails to comply with such requirements.

Limits the proprietary interest of a contractor in technical data generated in connection with the item to be procured to five years from the date of contract award.

Requires the competition advocate of the contracting defense agency to review within four years each designation of proprietary interest. Directs the advocate to remove any inappropriate designations.

Requires a bidder to state the extent of the proprietary interest expected to be claimed if awarded a procurement contract.

Directs the Secretary of Defense to promulgate regulations determining the manner the Department of Defense negotiates prices with nonproducing suppliers. Requires all suppliers to mark the name of the contractor, the stock number, and the original manufacturer of each item, and to include all technical data. Reduces from $500,000 to $100,000 the amount of a negotiated prime contract which requires the contractor to certify the accuracy of the cost data submitted.

Directs the head of each defense agency to designate an advocate for competition to promote competition in the procurement of property and services by such agency through review of activities and opportunities to achieve competition.

Directs defense agencies to procure supplies in quantities reflective of agency needs and which offer the total and unit cost most advantageous to the United States. Requires all bidders to state whether the quantity proposed is the most economically advantageous, and, if not, to put forth two quantities which would be more so.