STTR vs SBIR: Which Mechanism Fits Your University-Industry Partnership

The Core Decision: Who Performs the Research?

If you are a small business building technology that depends on university research capabilities — specialized equipment, faculty expertise, graduate student labor, or access to research facilities — the choice between SBIR and STTR is not cosmetic. It determines how much work your research partner can perform, who can serve as principal investigator, what IP agreements you need, and which agencies you can apply to.

Both programs fund early-stage R&D at small businesses. Both follow the Phase I (feasibility) to Phase II (development) structure. Both require U.S.-owned small businesses with fewer than 500 employees. The divergence is in how each program treats the relationship between the small business and a nonprofit research institution.

SBIR requires the small business to perform the majority of the work. A university can participate as a subcontractor or consultant, but its role is capped. STTR requires a formal partnership with a research institution. The university is not an optional add-on — it is a mandatory collaborator with guaranteed minimum work share.

This guide walks through the structural differences, work allocation rules, IP requirements, agency-level variations, and strategic scenarios that determine which mechanism serves a given partnership best. If you are forming a university spin-out, licensing faculty technology, or building a product that needs ongoing academic collaboration, the mechanism you choose will shape your proposal strategy, your budget, and your relationship with the research institution for years.

For current SBIR and STTR opportunities, explore small business grants on Granted.

Structural Differences: SBIR and STTR Side by Side

The table below captures the core structural differences. Each row represents a decision point that affects proposal strategy.

Dimension	SBIR	STTR
Research institution required?	No	Yes — must partner with a U.S. nonprofit research institution
Small business minimum work (Phase I)	67% of R&D costs	40% of R&D costs
Small business minimum work (Phase II)	50% of R&D costs	40% of R&D costs
Research institution minimum work	No minimum (subcontract capped at 33% Phase I, 50% Phase II)	30% of R&D costs
PI employment	Must be primarily employed by the small business	Can be employed by either the small business or the research institution
IP agreement required?	No (standard subcontract terms apply)	Yes — written Allocation of IP Rights agreement required
Participating agencies	11 federal agencies	6 federal agencies (DoD, DOE, HHS/NIH, NASA, NSF, USDA)
Set-aside percentage	3.2% of agency extramural R&D budget	0.45% of agency extramural R&D budget

The set-aside percentages matter. The SBIR pool is roughly seven times larger than the STTR pool. In dollar terms, the total SBIR program exceeds $3.5 billion annually while STTR accounts for roughly $500 million. This means STTR has fewer topics, fewer awards, and in some agencies, more competition per available dollar.

Under the 2026 reauthorization (Small Business Innovation and Economic Security Act, signed February 2026), these set-asides are scheduled to increase over seven years — SBIR rising to 7% and STTR to 1%. But the ramp is gradual, and agency implementation timelines remain unclear following the five-month lapse in program authority from October 2025 through February 2026.

Work Split Requirements: The Math That Drives Your Budget

The work split rules are the most operationally significant difference between the two programs. They dictate how you allocate budget between your company and the research institution, and they constrain your staffing plan.

SBIR Work Allocation

In SBIR Phase I, the small business must perform at least two-thirds (67%) of the R&D work, measured by total cost. That leaves a maximum of 33% for all subcontractors and consultants combined — not just the university, but any external party. In Phase II, the small business minimum drops to 50%, allowing up to 50% subcontracting.

Example: On a $250,000 SBIR Phase I, the small business must account for at least $167,500 in R&D costs. If a university lab is performing $60,000 of work and you also need a $15,000 testing subcontractor, you are at $75,000 in external costs (30%) — within limits. Add another $10,000 consultant and you hit $85,000 (34%), which violates the rule.

STTR Work Allocation

STTR Phase I requires the small business to perform at least 40% and the research institution at least 30% of R&D costs. The remaining 30% can be allocated to either party or to other subcontractors.

Example: On a $250,000 STTR Phase I, the minimum small business share is $100,000 and the minimum research institution share is $75,000. That leaves $75,000 in flexible allocation — it could go entirely to the university (bringing their share to 60%), split between both parties, or partially allocated to an outside subcontractor.

Practical Impact on Staffing

The work split requirements have direct consequences for who works on the project and where.

In an SBIR, your company's technical staff must be the primary performers. If the core innovation depends on a faculty member running experiments in a university lab using university equipment, fitting that work into a 33% subcontract ceiling may be impossible — or may force you to artificially restructure the work plan.

In an STTR, the university can perform up to 60% of the work. This accommodates scenarios where the research institution houses the key equipment, the essential personnel, or the specialized facilities that the small business cannot replicate. Faculty members can lead entire technical tasks without straining budget allocations.

The 40/30 split also creates a natural structure for the proposal's work plan: the small business owns integration, product development, and commercialization tasks; the research institution owns fundamental research, testing, and validation tasks. Reviewers expect to see this division clearly reflected in the statement of work.

Principal Investigator Rules: A Frequently Misunderstood Distinction

In SBIR, the principal investigator must be primarily employed by the small business at the time of award and for the duration of the project. "Primarily employed" means more than 50% of the PI's professional effort is dedicated to the small business. A university professor who consults for the company one day a week does not qualify.

In STTR, the PI can be primarily employed by either the small business or the research institution. This is a significant structural advantage for partnerships where the leading technical expert is a faculty member who has no intention of leaving their university appointment.

There are agency-specific nuances. NSF requires the STTR PI to be primarily employed by the small business — an exception to the general STTR rule. At DoD, NIH, NASA, and DOE, the PI can sit at either organization. Always check the specific solicitation, as agencies may impose additional requirements beyond the baseline program rules.

For early-stage university spin-outs where the founding technology came from a faculty member's lab, STTR often makes more sense precisely because the faculty PI can remain at the university. The alternative — having the professor shift primary employment to a startup that may have minimal revenue and no office — creates unnecessary friction and may not be credible to reviewers.

Intellectual Property: The Agreement You Cannot Skip

Every STTR proposal requires an Allocation of Intellectual Property Rights agreement between the small business and the research institution. This agreement must address three categories of IP:

Background IP: Technology, data, or know-how that each party brings to the project. The agreement must define what constitutes each party's background IP and confirm that each party retains ownership of its pre-existing assets.

Foreground (Project) IP: Inventions, software, data, and other intellectual property created during the funded project. The agreement specifies who owns what, based on inventorship and contribution. Under the Bayh-Dole Act framework that governs federally funded research, the general principle is: what we invent, we own; what you invent, you own; jointly created inventions are jointly owned.

Follow-on rights: Licensing terms for commercialization of project results, rights to conduct follow-on research, and provisions for managing jointly owned IP. This is where most negotiations stall.

A signed IP agreement is not required at proposal submission — but it must be fully executed before an agency will make an award recommendation. Starting negotiations after you receive a favorable review wastes time and puts your award at risk. Negotiate the agreement before you submit.

Common IP Negotiation Pitfalls

University technology licensing offices (TLOs) move slowly. Most TLOs handle hundreds of agreements annually with small staffs. An STTR IP allocation is not their highest priority. Begin the conversation at least three months before the submission deadline.

Exclusive licensing expectations collide. The small business typically wants exclusive rights to commercialize project results. The university wants to preserve its right to use project IP for research and education, and may want the option to license to others if the company fails to commercialize. These positions are both reasonable and must be reconciled in the agreement.

Joint ownership creates ambiguity. Under U.S. patent law, joint owners of a patent can each license the patent independently without the other's consent. Under copyright law, joint owners must share royalties. These default rules rarely serve either party well. The IP agreement should override them with explicit terms governing licensing, sublicensing, and revenue sharing for jointly owned IP.

Bayh-Dole compliance is non-negotiable. The federal government retains a royalty-free license to use any invention made under a federally funded project for government purposes. The agreement cannot override this. Both parties also have obligations to disclose inventions, elect title, and file patent applications within statutory timeframes.

In SBIR, IP is simpler. The small business is the prime contractor. If a university participates as a subcontractor, standard subcontract terms govern IP allocation, and the university's role is narrower. There is no statutory requirement for a separate IP allocation agreement. The small business owns project results, subject to Bayh-Dole.

Agency Landscape: Where STTR Exists and Where It Does Not

Only six federal agencies operate STTR programs: DoD, DOE, HHS (NIH), NASA, NSF, and USDA. If your target agency is EPA, DHS, DOT, DOC, or Education, STTR is not an option — you must use SBIR and structure any university involvement within the subcontracting limits.

Agency-by-Agency STTR Considerations

Department of Defense — The largest SBIR/STTR funder by dollar volume. DoD releases STTR topics alongside SBIR topics in its periodic solicitations, organized by military service and defense agency. STTR topics often focus on basic and applied research where university lab capabilities are essential — materials science, quantum computing, hypersonics, biodefense. DoD Phase I awards are typically $150,000-$250,000 with 6-12 month periods of performance.

National Institutes of Health — NIH STTR follows the same omnibus solicitation and peer review structure as NIH SBIR. Applications are reviewed by scientific study sections using the standard five-criterion scoring system. NIH STTR Phase I awards provide up to $275,000 in direct costs. A key advantage at NIH: STTR proposals can leverage the research institution's NIH-funded infrastructure and preliminary data, which strengthens the scientific premise.

National Science Foundation — NSF runs a combined SBIR/STTR program through America's Seed Fund (now America's Seed Fund powered by NSF). Important exception: NSF requires the STTR PI to be primarily employed by the small business, not the university. This eliminates one of STTR's primary advantages for university-led partnerships. NSF Phase I awards are up to $305,000.

Department of Energy — DOE STTR topics span clean energy, nuclear physics, high-energy physics, fusion, and advanced computing. University national laboratory partnerships are common in DOE STTR. Phase I awards typically range from $200,000-$250,000.

NASA — NASA STTR topics address specific technology needs identified by mission directorates. Phase I awards are $150,000 with a 13-month performance period. NASA STTR topics often require access to specialized research infrastructure — wind tunnels, radiation facilities, microgravity simulation — that universities and FFRDCs maintain.

USDA — The smallest STTR program by funding volume. Topics focus on agricultural technology, food safety, and rural development. Phase I awards are typically $100,000-$175,000.

Success Rates: What the Data Shows

Aggregated across all agencies, SBIR Phase I success rates average approximately 17%, with significant variation by agency. NSF reports the highest rates at roughly 20%. NIH Phase I success rates have fluctuated between 13% and 16% in recent fiscal years. DoD rates vary by topic and service branch.

STTR-specific success rate data is harder to isolate because many agencies report SBIR and STTR statistics together. Where data is available, STTR success rates tend to be comparable to or slightly higher than SBIR rates at the same agency. This likely reflects two factors: the smaller applicant pool (fewer companies have research institution partnerships in place) and the self-selection effect (companies that invest the effort to establish university partnerships and negotiate IP agreements tend to submit stronger proposals).

Phase II success rates are substantially higher — typically 30-60% depending on agency — because the pool of eligible applicants is limited to Phase I awardees and the agency has already validated the technical approach.

The practical takeaway: do not choose between SBIR and STTR based on success rates. Choose based on which mechanism fits your team structure, work plan, and partnership model. A well-structured proposal under the right mechanism will outperform a poorly structured proposal under either.

When STTR Is the Strategic Choice

STTR is the right mechanism when the university is not just helpful but essential. Specific scenarios:

The PI is a faculty member who will remain at the university. If the leading technical expert on the project is a professor who will not shift primary employment to the small business, STTR (at agencies other than NSF) is the only mechanism that allows them to serve as PI. Trying to structure this as an SBIR — with the professor as a consultant or co-investigator while a less-qualified company employee serves as PI — weakens the proposal.

The research requires university infrastructure. If the project depends on equipment, facilities, or research resources housed at the university — a cleanroom, an animal facility, a high-performance computing cluster, a clinical trial network — the work naturally belongs at the research institution. STTR's 30% minimum for the research institution (with the flexibility to allocate up to 60%) accommodates this. SBIR's 33% Phase I subcontracting cap may not.

The technology is being licensed from the university. In a classic university spin-out, the core IP originates from a faculty member's research. STTR formalizes the ongoing R&D collaboration and provides a framework for the IP relationship. The required Allocation of IP Rights agreement forces both parties to address ownership, licensing, and commercialization rights early — before conflicts arise.

The agency has STTR-specific topics aligned with your work. At DoD, STTR topics are distinct from SBIR topics. If the most relevant topic is an STTR topic, you must submit under the STTR mechanism. Trying to reshape the work to fit an SBIR topic is a losing strategy.

You need the university to perform more than 33% of Phase I work. This is the simplest quantitative test. If the research institution's contribution exceeds one-third of Phase I costs, SBIR does not work. STTR does.

When SBIR with a University Subcontract Is Sufficient

SBIR is the right mechanism when the small business can credibly perform the majority of R&D and the university's role is supplementary. Specific scenarios:

The university contribution is a discrete, bounded task. If a professor is running one set of validation experiments, performing materials characterization, or providing access to a specific instrument for a defined scope — and this work fits within the 33% subcontracting limit — a standard SBIR subcontract is cleaner and simpler.

You want to avoid the IP allocation agreement. For companies that already have clean IP ownership and do not want to negotiate an IP sharing arrangement with a university TLO, SBIR avoids this entirely. The subcontract includes standard IP provisions without requiring a separate allocation agreement.

The PI is employed by the small business. If your company has a qualified PI who will lead the project and the university researcher is supporting, SBIR's PI employment requirement is already met. There is no structural reason to use STTR.

Your target agency does not have an STTR program. Five of the eleven SBIR agencies — EPA, DHS, DOT, DOC, and Education — do not run STTR programs. If your target agency is one of these, SBIR with a university subcontract is the only path.

Faculty prefer to participate as consultants. A faculty member can work on an SBIR project as an individual consultant rather than as a representative of the university. This bypasses university overhead rates, avoids the TLO's involvement, and simplifies contracting. The trade-off: consultant agreements do not count as research institution partnerships and the work counts against the subcontracting limit, not a separate STTR allocation.

Budget Mechanics: How the Work Split Affects Your Numbers

The work split rules interact with indirect cost rates in ways that affect how much R&D you actually get for the award amount.

University indirect cost rates (also called facilities and administrative rates, or F&A rates) typically range from 45% to 65% of modified total direct costs for federally sponsored research. This means that for every $100 of direct research costs at the university, you pay an additional $45-$65 in overhead.

STTR budget example — $250,000 Phase I:

Party	Minimum share	Dollar amount
Small business (40% minimum)	40%	$100,000
Research institution (30% minimum)	30%	$75,000
Flexible allocation	30%	$75,000

If the university's negotiated F&A rate is 55% and the university performs 40% of the work ($100,000 total), approximately $35,500 of that goes to university overhead, leaving $64,500 for direct research costs (personnel, materials, equipment).

SBIR budget example — $250,000 Phase I with university subcontract:

The university subcontract cannot exceed $82,500 (33%). At the same 55% F&A rate, roughly $29,300 goes to overhead, leaving $53,200 for direct research costs at the university. The small business retains at least $167,500.

The higher university F&A rates eat into research dollars more aggressively in STTR because the university's share is larger. Some agencies cap the indirect cost rate that can be charged on subcontracts, and some universities offer reduced rates for SBIR/STTR projects. Negotiate the rate before finalizing your budget.

The 2026 Reauthorization: What Changed for STTR

The Small Business Innovation and Economic Security Act, signed into law in February 2026 after the programs lapsed for five months, introduced several changes relevant to STTR applicants:

Increased set-asides. The STTR set-aside is scheduled to rise from 0.45% to 1.0% of agency extramural R&D budgets over seven years. This roughly doubles the size of the STTR funding pool at full implementation, though the ramp is gradual and the effects will take time to materialize.

Strategic Breakthrough Awards. Agencies can now make awards up to $30 million with performance periods up to 48 months. These are available under both SBIR and STTR and are intended for technologies with high national security or public health impact. For STTR partnerships with significant university research components, the larger award ceiling creates new opportunities for ambitious multi-phase programs.

Enhanced due diligence. Every SBIR and STTR application now undergoes a due diligence review covering cybersecurity practices, patent portfolios, employee backgrounds, and financial ties to foreign countries of concern. For STTR applicants, this review extends to the research institution partnership. Ensure that your university partner and key personnel do not have foreign affiliations that would trigger additional scrutiny or disqualification.

Proposal caps. The reauthorization introduces limits on the number of proposals a single firm can submit per solicitation cycle. The specific caps vary by agency, but the intent is to reduce volume from serial applicants and improve the quality of the applicant pool.

Making the Decision: A Practical Framework

Answer these five questions to determine which mechanism fits your partnership:

1. Does the research institution need to perform more than 33% of Phase I work? If yes, STTR is the only option. SBIR cannot accommodate it.

2. Is the PI a faculty member who will remain employed at the university? If yes, STTR is strongly preferred (except at NSF, where the PI must be at the small business under both mechanisms).

3. Does your target agency have an STTR program? If no (EPA, DHS, DOT, DOC, Education), the question is moot — use SBIR.

4. Are you willing to negotiate an IP allocation agreement with the university? If the prospect of a multi-month negotiation with a university TLO is a dealbreaker, SBIR with a consultant or subcontract agreement avoids it.

5. Is there an STTR-specific topic aligned with your technology? At DoD especially, STTR topics are distinct. If the best-fit topic is STTR, submit STTR.

If you answered yes to questions 1 or 2, STTR is almost certainly the right choice. If you answered no to all five, SBIR is the simpler path.

Frequently Asked Questions

Can a small business submit both an SBIR and an STTR proposal for the same technology?

Yes, provided the proposals respond to different topics and the scopes of work are distinct. You cannot submit substantially the same proposal under both mechanisms for the same topic. Some agencies explicitly prohibit duplicate submissions across SBIR and STTR for the same solicitation. Check the specific solicitation rules — DoD, for example, allows companies to submit one proposal per topic, regardless of mechanism.

What qualifies as a "research institution" for STTR purposes?

The research institution must be a U.S.-based nonprofit. Eligible entities include colleges and universities, domestic nonprofit research organizations, and federally funded research and development centers (FFRDCs) such as national laboratories. For-profit research organizations, foreign universities, and individual consultants do not qualify, even if they perform research.

Does the STTR IP allocation agreement need to be finalized before proposal submission?

No. A signed agreement is not required at proposal submission. However, the agreement must be fully executed before the agency can make an award. Agencies typically give awardees a window (often 60-90 days after selection notification) to finalize the agreement. Starting negotiations early is strongly recommended — university TLOs are slow, and a stalled IP negotiation can delay or forfeit your award.

Can a company switch from SBIR to STTR (or vice versa) between Phase I and Phase II?

Generally yes, though it requires agency approval and a change in the partnership structure. If you completed an SBIR Phase I and now want to bring in a formal research institution partner for Phase II, you can propose Phase II as an STTR — provided the agency's Phase II solicitation allows it. The reverse is also possible. Discuss the transition with the program officer before submitting.

How does the STTR work split interact with cost-sharing or matching requirements?

STTR does not require cost-sharing or matching funds. The 40/30 split refers to the minimum percentage of the funded R&D that each party must perform — it is an allocation of the award dollars, not an obligation to contribute additional resources. If your proposal includes voluntary cost-sharing (some applicants offer it to demonstrate commitment), that cost-share can come from either party but does not change the minimum work allocation requirements.

Granted helps small businesses and research teams find the right SBIR and STTR opportunities and build competitive proposals from the start.