Verification represents the next step in the evolution of the impact investing industry, bringing added credibility to the marketplace and holding all impact investors accountable to a shared set of standards, principles, and best practices.

Click below to download Tideline’s benchmark report on impact verification.

Making the Mark: Investor Alignment with the
Operating Principles for Impact Management


What is impact verification?

Impact verification is the review and assurance of an investor’s impact performance or impact management practices against specific industry standards. Typically, this verification would be completed by an independent specialist or an accredited verification provider.

The Operating Principles for Impact Management (“OPIM” or “the Principles”) are one such set of standards for impact management that require all signatories to independently verify their alignment with the Principles.


The benefits of verification

We believe that verification brings three important benefits to the impact investing market:

  • Discipline – verification encourages impact investors to take steps to adopt industry best practices, continuously raising the bar for performance across the industry 
  • Accountability – verification provides a mechanism for evaluating if impact investors’ actions and results are consistent with their claims, ensuring greater transparency and credibility across the market 
  • Comparability – verification allows stakeholders, whether asset owners, intermediaries, or beneficiaries, to evaluate different approaches to impact investing using consistent frameworks and benchmarks


Tideline’s verification methodology

We began developing our methodology in early 2019, building on the firm’s experience as an impact investing consultant for a wide range of asset managers and asset owners. We started with a process to verify investor alignment with the Principles, which were formally introduced in April 2019. We designed our methodology to be rigorous, efficient, and actionable, relying on a three-step process: Learn, Assess, and Review.

Our comprehensive assessment provides investors and their stakeholders with a holistic picture of their impact management system, helping impact investors understand and institute best practices rather than simply ‘checking the box’ to comply with a verification requirement.


Additional Resources

Here are some additional resources to learn more about Tideline’s approach as well as verification in general.

Tideline resources




Industry resources

B Lab –

Impact Management Project (IMP) – 

Global Impact Investing Network (GIIN) – 

Operating Principles for Impact Management (OPIM or ‘the Principles’) – 

Principles for Responsible Investment (PRI) – 

SDG Impact –



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