Hi,
there is many way to do this, but we do not recommend changing the source code.

You can archive this by:
1. In your select search field set DB parameter to get all company names as options (screenshot 1)
With this you will have a search select field with all company names options, but this field search into their values not on values of company_name text field, so follow step 2

2. You can create a simple plugin to copy company_name value into company_name_search values, follow these steps:
- Download, install and enable our skeleton plugin, you will find this at the end of page https://www.easy-profile.com/docs/44-triggers.html
- Open file /plugins/jsn/skeleton/skeleton.php
- Delete samples functions like: triggerFieldAvatarUpdate and triggerProfileUpdate
- write your function to copy field value:

triggerProfileUpdate($user,&$data,$changed,$isNew){ 

  if(in_array('company_name',$changed)){ 

    $data['company_name_search']=$data['company_name'];

  } 

}

Now when user register or update his profile Easy Profile store in DB the company name in 2 columns (company_name,company_name_search). Now search select field can search in own value because filled by this plugin

3. this not work for pre-existing users, the copy of the field value comes only when user updated a profile. You need to copy manually values from column "company_name" to column "company_name_search", you can do this with a simple query launched from some SQL tools like PhpMyAdmin. Here is a simple query that you can use to do this: http://stackoverflow.com/questions/6308594/copy-data-from-column-to-another-column-on-the-same-table

NOTE: this code is not tested and not supported, this is only for example purpose.

Awesome, thank you so much for your reply. That looks to be a much better way to do it, thank you.

Sorry to throw another (small) question at you.. but on a related matter, which you previously helped me with, is there a way to edit this user list sql query to prevent the current/logged in user appearing in the list?

company_name LIKE "{user company_name displayedOrMe}" AND company_name IS NOT NULL AND company_name<>''

Many thanks.

Note - update on the skeleton plugin solution;

triggerProfileUpdate($user,&$data,$changed,$isNew){ 

  if(in_array('company_name',$changed)){ 

    $data['company_name_search']=$data['company_name'];

  } 

}

It's not searchable. I can see the table data is being copied over but I think the problem is the format.
The input is via a text field (e.g. My Company Name) but the select list requires an array style format (e.g. ["My Company Name"]).

Changing this line seems to work ok.. $data['company_name_search']='["'.$data['company_name'].'"]';