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Fake POC ( Proof of coins ) using Blockchain wallet
https://steemit.com/crypto/@luciotrader/6mvgvi-being-an-otc-agent-fake-poc-proof-of-coins-using-blockchain-wallet.

So what is a Satoshi

The Satoshi is currently the smallest unit of the bitcoin currency recorded on the blockchain.[1] It is a one hundred millionth of a single bitcoin (0.00000001 BTC).[1] The unit has been named in collective homage to the original creator of Bitcoin, Satoshi Nakamoto.
In OTC trading Satoshi also means a small amount( not necessarily 0.00000001).

Preface

Lots of time people wonder why the f**k can't the seller send a Satoshi or a signed message to the buyer to prove he holds the coins?

Personal experience

The first big OTC trade that me and my partners were working on was with a very respectful connector (mandate for the buyers). The guy knows a lot of buyers who are willing to buy 5K+ BTC but in order to trade they have only one little request, let's guess... and yes it's for a Satoshi! The people are allegedly ready with the money and can transfer it to Hong Kong without any problem. The mandate is also willing to show us POF (proof of funds) bank statements and videos so we will know that he has serious buyers (We will talk about POF in another article). We were really optimistic about it because you know ... what's the problem for the seller who holds the coins to send a Satoshi? We checked with our network of crypto friends...we were able to find some sellers but none of them were willing to send a Satoshi! We thought to ourselves "WTF!". Even though we showed them a "great" POF, they were unwilling to send a Satoshi or a signed message.

After some time, we came to realize what's really going on! So ... in the past, sellers really used to send Satoshis but they stopped for various of reasons ( there are still some sellers willing to send a Satoshi but usually only in a really advanced stage of the deal).

Bastard middlemen

Surprisingly the first reason for making life difficult for middlemen comes from the middlemen themselves. Like a self-destructive mechanism. How come?

A middleman finds a seller who is willing to sell for 6% below the market rate. He asks the seller to send him a satoshi, pretending that there is indeed a buyer who is ready to move funds into escrow. The buyer is presented as the "King of England" or "Bittrex Exchange" etc. The truth is that he has no buyer yet!

After getting the Satoshi, the middleman is starting to look for a real buyer, but ... guess what? It is not that easy to find a real buyer!

Technical aspect

So we all know that submitting a transaction to the blockchain from our wallet is an easy task ... well, think again :).
When sending a transaction the transaction is being sent from a specific address or group of addresses attached to our wallet, like the saying "Don't put all your eggs in one basket" seller or group of sellers will not put all of their bitcoin in one of their addresses it makes no sense for them to do so .... why? if you don't know the answer please google it.
So the process of uniting bitcoins from different addresses to one address is time-consuming and usually people with this amount of bitcoins don't have it plus ..., time is money!.

Sync

Some sellers use wallets like bitcoin core which take time to sync, and like we said before time is money.

Accessibility

Some bitcoin wallets containing an enormous amount of coins being deposit at the seller's trustee office safe box, so accessing them does require some procedure which again takes time.

Security

OTC is a dangerous world and the sellers know it, they wouldn't like to volunteer a lot of info to the "buyers" even when in a very advanced part of the deal. Some buyers are fake and only try to get info about real sellers in order to try to steal their coins or use these details to steal others money. when the seller sends a satoshi it does prove to the buyer that the seller really holds the coins... so we might "whatever" - so the 'buyer' knows what the hell is the problem ... well :
Blackmail - some buyers are fake and can try something criminal in order to get possession of the coins, harassing the seller, kidnap for ransom purpose and so on. Hacking and Phishing - some of our beloved buyers are actually hackers while having the info of the seller and the address attached they will try some kind of manipulations in order to get the private keys.

One more point

Sometimes even after the sellers get all the info from the buyer (KYC, LOI, POF) they still won't send a satoshi but might do it only after signing the contract... and why is that? We personally witnessed a case where the buyer had all the documents sent to the seller and he was asking for some satoshi afterward...but, in fact, they were not the real documents. The buyer was pretending to be someone else. We can presume his real intentions were to try to resell the BTC to another buyer or simply to try to steal this other person's money by convincing him that he holds those BTC.

Conclusion

Real seller/s will not send a Satoshi.