Alright, here is how ActivTrades probably replied to your question of whether they have a dealing desk or not.
They say, quote:
"We don't have any dealing desk. We operate in an OTC environment."

Now, an OTC (Over the Counter) simply means that a trader is trading the market with a dealer, who facilitates buy and sell orders by either electronic network or by phone instead of an physical trading floor.
So, I asked them again, and here is the final reply, which clarifies the point, quote:

"We don't have any dealing desk. An OTC market is a market without clearing house so we act as market maker on the products we offer. However we also offer futures products on the exchange market and in that case you can trade through us electronically on the exchange with a clearing house overseeing trades."

Here is again what ActivTrades says:
"...The spreads for the standard accounts are fixed, as you can see in our Demo.
The scalper account has variable spreads, according to our liquidity provider conditions.

The Scalping Account is designed for short term, high frequency, economic news trading and other aggressive trading styles... "

Hi BG

Do you any scalping experience with activtrades's interbank account?

Thank You!