Interim HR Manager

Flagship Pioneering, Inc.•Cambridge, MA

3d•$40 - $100•Onsite

About The Position

Flagship Pioneering is seeking an Interim HR Manager to provide full-cycle HR support to a portfolio of multiple early-stage life sciences companies during a planned leave of absence. The role is the primary HR resource for companies with approximately 1 to 15 employees, each at a different stage of building its people infrastructure. It calls for an experienced HR manager who can work autonomously, thrive in ambiguity, switch rapidly between organizations, and prioritize competing needs. The position is approximately five months in duration and is on-site four days per week in Cambridge, Massachusetts. It reports to the Senior HR Business Partner. The role provides day-to-day employee lifecycle and HR operations support, collaborates with cross-functional partners to maintain consistency and compliance, and assists the Senior HR Business Partner with administrative work. The salary range is listed as $40 - $100; the posting does not specify the pay period or currency.

Requirements

At least 5 years of HR generalist and/or business partner experience, ideally supporting multiple business units or startup-stage companies simultaneously.
Strong working knowledge of multi-state employment law and HR compliance requirements.
Prior experience in biotech, life sciences, pharmaceuticals, or fast-growing startup environments.
Experience supporting companies in early stages of HR infrastructure build-out, including environments without a handbook or formal processes.
Ability to operate independently with minimal direction and manage competing priorities across organizations.
Strong command of confidential matters, data-driven decision-making, and interpersonal communication.

Nice To Haves

SHRM-CP/SCP or PHR/SPHR certification.

Responsibilities

Deliver day-to-day HR services, including onboarding, performance management, employee relations, and offboarding across portfolio companies.
Maintain HR records and ensure data integrity across HRIS and other people systems.
Assist with compensation benchmarking, job leveling, and offer structuring as new roles are created.
Coordinate with Talent Acquisition, Payroll, Legal, and Learning & Development to maintain consistency across portfolio companies.
Ensure companies remain compliant with applicable federal, state, and local employment laws, partnering with outside counsel as needed.
Provide general HR administrative support to the Senior HR Business Partner, including scheduling, document management, tracking action items, and coordinating across portfolio companies.