Determining precisely who shared your Instagram post to their own feed or directly to other users via direct message is generally not possible through Instagram's native features.
Direct Sharing Visibility
Instagram does not provide a list of individual users who have shared your post using the "Send to" (paper airplane icon) feature, unless they share it to their Story and tag you.
- Shares to Stories: If someone shares your feed post to their Instagram Story and tags your account, you will receive a notification and be able to see their Story (provided their account is public or you follow them if it's private). This is the most direct way to see a specific user sharing your content.
- No Direct User List for Other Shares: For shares via direct message or to other platforms, Instagram does not reveal the sharer's identity.
What You Can See
While you can't see who shared in most cases, you can see how many times your post has been shared if you have a Professional (Business or Creator) account:

- Post Insights: Navigate to your post, tap "View Insights" (below the image/video). Here, you might see a "Shares" metric, indicating the number of times your post was shared to Stories or sent as a message. This is an aggregate number and doesn't identify individuals.
Indirect Indicators
Although not a direct "who shared" list, you might infer sharing activity through:
- Increased Engagement: A sudden spike in likes, comments, or new followers after posting could indicate your content is being shared and reaching a wider audience.
- Comments Mentioning Shares: Users might occasionally comment "Shared!" or "Sent this to my friend."
- Being Tagged in Resposts: If users screenshot and repost your content to their feed (rather than using the share feature) and tag you, you'll be notified.
In summary, Instagram prioritizes user privacy regarding direct sharing actions. You can see shares to Stories if you are tagged and view aggregate share counts with a professional account, but a comprehensive list of every individual who shared your post is not available.