Final answer:
The PRI is a global network of investors committed to sustainable investment by including ESG factors in their practices. The specific number of asset owners signed to the PRI varies over time. As of early 2023, there were over 3,000 signatories, but for the latest figures, refer to the PRI's official communication channels.
Step-by-step explanation:
The Principles for Responsible Investment (PRI) is a United Nations-supported network of investors working together to promote sustainable investment through the incorporation of environmental, social, and corporate governance (ESG) factors into their decision-making and ownership.
The exact number of asset owners that are signatories to the PRI can change as new signatories join and others leave. As of my knowledge cutoff date in early 2023, there were over 3,000 organizations worldwide that had become signatories to the PRI, but for the most current number, one would need to refer to the latest data provided directly by the PRI on their official website or through their annual reports.