Instead of asking for recommendations, this is what I would do in your case:
1. First go here: https://www.blackhatworld.com/forums/seo-link-building.43/
2- Search for link indexing services, like Elitelinkindexer (there are some BSTs there). PM the creators and ask for a quotation for such amount of links (it may cost you around $2K easily).
3. Pick like 1-2K links per service and send them indexing in many of those services. Then use a web server logger to check if spiders are going through such links (and see referrals to confirm they come from them).
4. And choose the one that gives you best price/best % indexing results ratio
Rather than submitting all 5 million links at once, it's recommended that you drip feed your links over a period of time. This will help ensure that your links are indexed slowly and naturally, which is more likely to be effective.Hello, how to get such a massive amount of links indexed? I'm looking for service that will allow me to submit 5 million links at once within single campaign and let me drip feed that for lets say 30 to 90 days. Any suggestions?
Have you seen the prices of the current indexing services? You're looking at around $0.05 - $0.50 per link with most of the marketplace services. But these are the ones that work.Thanks buddy but this is not exactly what I'm looking for2K? Are you having a laugh?