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  "data": {
    "topic": "invention-assignment",
    "state": "south-dakota",
    "frontmatter": {
      "title": "Employee Invention Assignment in South Dakota",
      "description": "South Dakota has no employee-invention-assignment carve-out statute, but it is not a blank-slate state — SDCL § 60-2-10, a Field Code provision, gives the employer whatever an employee acquires by virtue of employment, and the South Dakota Supreme Court in Rural Pennington County Tax Ass'n v. Dier refused to read it as an employer-ownership invention statute. Absent an express or implied agreement the inventor owns. A post-employment holdover clause faces a duality — reasonableness scrutiny if narrow and trade-secret-tethered, outright voidness under SDCL § 53-9-8 if it functions as a de facto noncompete.",
      "state": "South Dakota",
      "lastReviewed": "2026-07-02",
      "license": "CC BY 4.0",
      "authors": [
        "steven-obiajulu"
      ],
      "summary": {
        "bottomLine": "South Dakota has no invention-assignment carve-out statute, and although SDCL § 60-2-10 gives the employer whatever an employee acquires by virtue of employment, the South Dakota Supreme Court in Dier refused to read it as an employer-ownership invention statute — absent an express or implied agreement the inventor owns an own-time invention; no notice regime exists; a post-employment holdover clause would face reasonableness-and-severability scrutiny under Rezatto if narrow and trade-secret-tethered, but risks being void under SDCL § 53-9-8 if it functions as a de facto noncompete.",
        "keyLaw": "SDCL § 60-2-10; Rural Pennington County Tax Ass'n v. Dier, 515 N.W.2d 841 (S.D. 1994); SDCL § 53-9-8",
        "statutoryCarveOut": "none",
        "defaultOwnership": "employee",
        "employeeNoticeRequired": "n/a",
        "holdoverClauseLimit": "reasonablenessOnly",
        "carveOutScope": "South Dakota has no statutory own-time carve-out; SDCL § 60-2-10 is an employer-flavored Field Code default-ownership provision rather than a limit on assignment clauses, and Dier construed it against employer ownership of an own-time, own-resource invention, so an assignment clause is bounded by ordinary contract law, the common-law inventor-owns default, and the restraint-of-trade limits of SDCL § 53-9-8."
      },
      "about": [
        "South Dakota invention assignment",
        "SDCL 60-2-10 products of employment",
        "Rural Pennington County Tax Association v. Dier",
        "South Dakota employee invention ownership",
        "SDCL 53-9-8 restraint of trade",
        "1st American Systems v. Rezatto",
        "South Dakota holdover trailing assignment"
      ],
      "translations": [
        {
          "language": "中文",
          "status": "planned"
        },
        {
          "language": "Español",
          "status": "planned"
        },
        {
          "language": "Português",
          "status": "planned"
        },
        {
          "language": "Deutsch",
          "status": "planned"
        }
      ],
      "relatedForm": {
        "slug": "openagreements-confidentiality-invention-assignment-agreement"
      }
    },
    "questions": [
      {
        "slug": "statutory-carve-out",
        "label": "Can the employer require assignment of every invention?",
        "heading": "Can a South Dakota employer require assignment of every invention?",
        "answerText": "There is no statutory ceiling — but South Dakota is not a blank-slate state. No South Dakota statute carves own-time, own-resource inventions out of an assignment clause the way California or Washington law does. What South Dakota does have is SDCL § 60-2-10, a Field Code provision under which anything an employee acquires by virtue of employment belongs to the employer — an employer-flavored default-ownership rule, not a carve-out — and the South Dakota Supreme Court has already refused to read it as an employer-ownership invention statute where the invention was developed on the employee's own time.",
        "sources": [
          {
            "id": "sd-60-2-10-employer-default",
            "authorityType": "primary-law",
            "tier": "primary-source-backed",
            "title": "SDCL § 60-2-10 — Products of employment belong to employer",
            "citation": "SDCL § 60-2-10.",
            "url": "https://sdlegislature.gov/Statutes/60-2-10",
            "proposition": "SDCL § 60-2-10 supports the rule that South Dakota's only employment-IP statute is an employer-flavored Field Code default — anything an employee acquires by virtue of employment belongs to the employer — not a California-style carve-out limiting what an assignment clause may reach.",
            "verbatimQuote": "Anything that an employee acquires by virtue of employment, lawfully or unlawfully, during or after the term of employment belongs to the employer, excepting any compensation due the employee.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-sd-60-2-10-employer-default"
          },
          {
            "id": "dier-no-ownership-agreement",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Rural Pennington County Tax Ass'n v. Dier",
            "citation": "Rural Pennington County Tax Ass'n v. Dier, 515 N.W.2d 841 (S.D. 1994).",
            "url": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/",
            "deepLink": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/#:~:text=No%20express%20or%20implied%20agreement,by%20Dier%20has%20been%20established.",
            "proposition": "Rural Pennington County Tax Ass'n v. Dier supports the rule that SDCL § 60-2-10 does not operate as a self-executing employer-ownership invention statute — the court required an express or implied ownership agreement and found none, so the employer took nothing in an invention developed on the employee's own time.",
            "verbatimQuote": "No express or implied agreement as to Pennington County’s ownership of inventions developed by Dier has been established.",
            "date": "1994-05-11",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-dier-no-ownership-agreement"
          }
        ]
      },
      {
        "slug": "employee-notice",
        "label": "Must the employer give the employee written notice of the carve-out?",
        "heading": "Must a South Dakota employer notify the employee?",
        "answerText": "Not applicable. Because South Dakota has no invention-assignment carve-out statute, there is no statutory line for a notice to mark and no notice requirement of the kind California imposes under Labor Code § 2872 or Washington imposes under RCW 49.44.140(3). The only employment-IP statute on the books, SDCL § 60-2-10, is a default-ownership provision that contains no notice, disclosure, or acknowledgment formality of any kind.",
        "sources": [
          {
            "id": "sd-60-2-10-no-notice",
            "authorityType": "primary-law",
            "tier": "primary-source-backed",
            "title": "SDCL § 60-2-10 — Products of employment belong to employer",
            "citation": "SDCL § 60-2-10.",
            "url": "https://sdlegislature.gov/Statutes/60-2-10",
            "proposition": "SDCL § 60-2-10 supports the conclusion that South Dakota imposes no invention-assignment notice or disclosure formality — the state's only employment-IP statute allocates default ownership and contains no notice requirement, and no carve-out statute exists for a notice to describe.",
            "verbatimQuote": "Anything that an employee acquires by virtue of employment, lawfully or unlawfully, during or after the term of employment belongs to the employer, excepting any compensation due the employee.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-sd-60-2-10-no-notice"
          }
        ]
      },
      {
        "slug": "default-ownership",
        "label": "Absent a written assignment, who owns the invention?",
        "heading": "Who owns an invention by default in South Dakota?",
        "answerText": "The employee, unless hired to invent — and unlike most states without a carve-out statute, South Dakota has on-point state supreme-court authority saying so. In Rural Pennington County Tax Ass'n v. Dier, the South Dakota Supreme Court adopted the common-law rule that mere general employment gives the employer no exclusive rights to an employee's invention, quoting the Corpus Juris Secundum summary of the rule with approval and citing United States v. Dubilier Condenser Corp., and it construed SDCL § 60-2-10 consistently with that default.",
        "sources": [
          {
            "id": "dier-common-law-default",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Rural Pennington County Tax Ass'n v. Dier",
            "citation": "Rural Pennington County Tax Ass'n v. Dier, 515 N.W.2d 841 (S.D. 1994) (quoting 30 C.J.S. Employer-Employee § 117 (1992)).",
            "url": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/",
            "deepLink": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/#:~:text=In%20the%20absence%20of%20an,given%20to%20his%20employer%E2%80%99s%20business.",
            "proposition": "Rural Pennington County Tax Ass'n v. Dier adopts the common-law default for South Dakota — quoting with approval the Corpus Juris Secundum summary that, absent an express or implied ownership agreement, general employment gives the employer no exclusive rights to the employee's inventions — and construes SDCL § 60-2-10 consistently with that rule, citing United States v. Dubilier Condenser Corp.",
            "verbatimQuote": "In the absence of an express or implied agreement as to the ownership of inventions of the employee, the employer from the mere fact of a general employment has no exclusive rights to the inventions of his employee, even though in order to perfect his invention the employee uses his employer’s property, or receives the assistance of others in the employer’s pay, or takes time which should have been given to his employer’s business.",
            "date": "1994-05-11",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-dier-common-law-default"
          },
          {
            "id": "dier-own-time-facts",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Rural Pennington County Tax Ass'n v. Dier",
            "citation": "Rural Pennington County Tax Ass'n v. Dier, 515 N.W.2d 841 (S.D. 1994).",
            "url": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/",
            "deepLink": "https://www.courtlistener.com/opinion/2135639/rural-pennington-county-tax-assn-v-dier/#:~:text=Nothing%20in%20the%20record%20establishes%20that%20county,to%20any%20degree%20of%20significance.",
            "proposition": "Rural Pennington County Tax Ass'n v. Dier expressly rested on the absence of significant employer resources, so whether SDCL § 60-2-10 vests outright employer ownership in a resource-heavy, employer-time invention remains an open question the case did not decide.",
            "verbatimQuote": "Nothing in the record establishes that county resources were utilized to any degree of significance.",
            "date": "1994-05-11",
            "pullQuoteLocator": "Nothing in the record establishes that county|to any degree of significance.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-dier-own-time-facts"
          },
          {
            "id": "stanford-inventor-baseline",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Bd. of Trustees of the Leland Stanford Junior Univ. v. Roche Molecular Systems",
            "citation": "Bd. of Trustees of the Leland Stanford Junior Univ. v. Roche Molecular Sys., Inc., 563 U.S. 776 (2011).",
            "url": "https://www.courtlistener.com/opinion/218133/board-of-trustees-of-the-leland-stanford-junior-university-v-roche/",
            "deepLink": "https://www.courtlistener.com/opinion/218133/board-of-trustees-of-the-leland-stanford-junior-university-v-roche/#:~:text=Since%201790%2C%20the%20patent%20law,invention%20belong%20to%20the%20inventor.",
            "proposition": "Stanford v. Roche confirms the long-standing premise of U.S. patent law that rights in an invention belong to the inventor, the baseline against which any South Dakota assignment clause or statutory default is measured.",
            "verbatimQuote": "Since 1790, the patent law has operated on the premise that rights in an invention belong to the inventor.",
            "date": "2011-06-06",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-stanford-inventor-baseline"
          },
          {
            "id": "dubilier-hired-to-invent",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "United States v. Dubilier Condenser Corp.",
            "citation": "United States v. Dubilier Condenser Corp., 289 U.S. 178 (1933).",
            "url": "https://www.courtlistener.com/opinion/1087847/united-states-v-dubilier-condenser-corp/",
            "deepLink": "https://www.courtlistener.com/opinion/1087847/united-states-v-dubilier-condenser-corp/#:~:text=One%20employed%20to%20make%20an,his%20employer%20any%20patent%20obtained.",
            "proposition": "United States v. Dubilier Condenser Corp. — cited directly in Dier — holds that an employee hired to make an invention who succeeds during the term of service is bound to assign the resulting patent to the employer.",
            "verbatimQuote": "One employed to make an invention, who succeeds, during his term of service, in accomplishing that task, is bound to assign to his employer any patent obtained.",
            "date": "1933-05-08",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-dubilier-hired-to-invent"
          }
        ]
      },
      {
        "slug": "holdover-clause-limit",
        "label": "Are post-employment trailing-assignment clauses enforceable?",
        "heading": "Are trailing-assignment (holdover) clauses enforceable in South Dakota?",
        "answerText": "It depends on how broad the clause is, because South Dakota's restraint-of-trade statute creates a real voidness risk. No South Dakota decision found in our review addresses a post-employment invention-assignment clause. SDCL § 53-9-8 voids contracts restraining a lawful profession, trade, or business except for the narrow exceptions in §§ 53-9-9 to 53-9-12, and none of those exceptions covers invention assignment. The likeliest analysis splits in two: a narrow holdover tethered to the employer's trade secrets would face reasonableness scrutiny under the framework of 1st American Systems, Inc. v. Rezatto, while a broad holdover that functions as a de facto noncompete risks being void outright under § 53-9-8.",
        "sources": [
          {
            "id": "sd-53-9-8-void",
            "authorityType": "primary-law",
            "tier": "primary-source-backed",
            "title": "SDCL § 53-9-8 — Contracts in restraint of trade void",
            "citation": "SDCL § 53-9-8.",
            "url": "https://sdlegislature.gov/Statutes/53-9-8",
            "proposition": "SDCL § 53-9-8 supports the rule that South Dakota's baseline for restraints of trade is voidness — any contract restraining a lawful profession, trade, or business is void to that extent unless it fits one of the closed statutory exceptions in §§ 53-9-9 to 53-9-12, none of which covers invention assignment.",
            "verbatimQuote": "Any contract restraining exercise of a lawful profession, trade, or business is void to that extent, except as provided by §§ 53-9-9 to 53-9-12, inclusive.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-sd-53-9-8-void"
          },
          {
            "id": "sd-53-9-11-two-year-box",
            "authorityType": "primary-law",
            "tier": "primary-source-backed",
            "title": "SDCL § 53-9-11 — Employment contract competition limitation",
            "citation": "SDCL § 53-9-11.",
            "url": "https://sdlegislature.gov/Statutes/53-9-11",
            "proposition": "SDCL § 53-9-11 supports the rule that South Dakota's only employment exception to the voidness baseline is a noncompete or customer nonsolicit capped at two years from termination — the box a holdover clause operating as a restraint on working in the field would have to fit.",
            "verbatimQuote": "Except as otherwise provided in § 53-9-11.2, an employee may agree with an employer at the time of employment or at any time during employment not to engage directly or indirectly in the same business or profession as that of the employer for any period not exceeding two years from the date of termination of the agreement and not to solicit existing customers of the employer within a specified county, first- or second-class municipality, or other specified area for any period not exceeding two years from the date of termination of the agreement, if the employer continues to carry on a like business therein.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-sd-53-9-11-two-year-box"
          },
          {
            "id": "rezatto-reasonableness-test",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "1st American Systems, Inc. v. Rezatto",
            "citation": "1st American Systems, Inc. v. Rezatto, 311 N.W.2d 51 (S.D. 1981) (quoting Blake, Employee Agreements Not to Compete, 73 Harv. L. Rev. 625 (1960)).",
            "url": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/",
            "deepLink": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/#:~:text=%5BA%5D%20covenant%20is%20reasonable%20only,not%20injurious%20to%20the%20public.",
            "proposition": "1st American Systems, Inc. v. Rezatto supports the reasonableness path for IP-protective covenants that are not pure noncompetes — the court enforced a nondisclosure covenant severed from a void noncompete, adopting a three-part reasonableness test from Blake's Harvard Law Review article.",
            "verbatimQuote": "[A] covenant is reasonable only if it (1) is no greater than required for the protection of the employer, (2) does not impose undue hardship on the employee and (3) is not injurious to the public.",
            "date": "1981-10-14",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-rezatto-reasonableness-test"
          },
          {
            "id": "rezatto-void-only-to-extent",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "1st American Systems, Inc. v. Rezatto",
            "citation": "1st American Systems, Inc. v. Rezatto, 311 N.W.2d 51 (S.D. 1981).",
            "url": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/",
            "deepLink": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/#:~:text=Finally%2C%20SDCL%2053%2D9%2D8%20provides%20that,is%20a%20restraint%20of%20trade.",
            "proposition": "1st American Systems, Inc. v. Rezatto supports severability — SDCL 53-9-8 voids a contract only to the extent it restrains trade, so a void noncompete does not drag down a divisible, reasonable IP-protective covenant.",
            "verbatimQuote": "Finally, SDCL 53-9-8 provides that the contract is void only to the extent that it is a restraint of trade.",
            "date": "1981-10-14",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-rezatto-void-only-to-extent"
          },
          {
            "id": "zakinski-narrow-construction",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Central Monitoring Service, Inc. v. Zakinski",
            "citation": "Central Monitoring Service, Inc. v. Zakinski, 1996 SD 116, 553 N.W.2d 513.",
            "url": "https://www.courtlistener.com/opinion/899991/central-monitoring-service-inc-v-zakinski/",
            "deepLink": "https://www.courtlistener.com/opinion/899991/central-monitoring-service-inc-v-zakinski/#:~:text=Such%20exceptions%20must%20be%20construed,contracts%20in%20restraint%20of%20trade.",
            "proposition": "Central Monitoring Service, Inc. v. Zakinski supports strict construction of the § 53-9-8 exceptions — they must be read narrowly to promote the prohibition on restraints of trade, the lens a court would bring to any argument that a holdover clause slips past the statute.",
            "verbatimQuote": "Such exceptions must be construed narrowly so as to promote the prohibition against contracts in restraint of trade.",
            "date": "1996-09-04",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-zakinski-narrow-construction"
          },
          {
            "id": "sd-53-9-8-void-practice",
            "authorityType": "primary-law",
            "tier": "primary-source-backed",
            "title": "SDCL § 53-9-8 — Contracts in restraint of trade void",
            "citation": "SDCL § 53-9-8.",
            "url": "https://sdlegislature.gov/Statutes/53-9-8",
            "proposition": "SDCL § 53-9-8 supports the drafting risk that a broad holdover clause operating as a de facto noncompete is void to that extent unless it fits a closed statutory exception, none of which covers invention assignment.",
            "verbatimQuote": "Any contract restraining exercise of a lawful profession, trade, or business is void to that extent, except as provided by §§ 53-9-9 to 53-9-12, inclusive.",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-sd-53-9-8-void-practice"
          },
          {
            "id": "rezatto-reasonableness-test-practice",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "1st American Systems, Inc. v. Rezatto",
            "citation": "1st American Systems, Inc. v. Rezatto, 311 N.W.2d 51 (S.D. 1981) (quoting Blake, Employee Agreements Not to Compete, 73 Harv. L. Rev. 625 (1960)).",
            "url": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/",
            "deepLink": "https://www.courtlistener.com/opinion/2193337/1st-american-systems-inc-v-rezatto/#:~:text=%5BA%5D%20covenant%20is%20reasonable%20only,not%20injurious%20to%20the%20public.",
            "proposition": "1st American Systems, Inc. v. Rezatto supports drafting a holdover clause to survive reasonableness review — no greater than required to protect the employer, no undue hardship on the employee, and not injurious to the public — the test the court adopted from Blake's Harvard Law Review article for a covenant severed from a void noncompete.",
            "verbatimQuote": "[A] covenant is reasonable only if it (1) is no greater than required for the protection of the employer, (2) does not impose undue hardship on the employee and (3) is not injurious to the public.",
            "date": "1981-10-14",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-rezatto-reasonableness-test-practice"
          },
          {
            "id": "zakinski-narrow-construction-practice",
            "authorityType": "case-law",
            "tier": "primary-source-backed",
            "title": "Central Monitoring Service, Inc. v. Zakinski",
            "citation": "Central Monitoring Service, Inc. v. Zakinski, 1996 SD 116, 553 N.W.2d 513.",
            "url": "https://www.courtlistener.com/opinion/899991/central-monitoring-service-inc-v-zakinski/",
            "deepLink": "https://www.courtlistener.com/opinion/899991/central-monitoring-service-inc-v-zakinski/#:~:text=Such%20exceptions%20must%20be%20construed,contracts%20in%20restraint%20of%20trade.",
            "proposition": "Central Monitoring Service, Inc. v. Zakinski supports the drafting expectation that a South Dakota court will construe the § 53-9-8 exceptions narrowly, so an overbroad holdover is more likely to be severed or voided than saved by a generous reading of the exceptions.",
            "verbatimQuote": "Such exceptions must be construed narrowly so as to promote the prohibition against contracts in restraint of trade.",
            "date": "1996-09-04",
            "anchor": "https://openagreements.org/practice-guides/invention-assignment/us/south-dakota#src-zakinski-narrow-construction-practice"
          }
        ]
      }
    ]
  }
}