Q:

Copyright on derived software under EPL license v1.0

I recently modified software code licensed under EPL v1.0. Can I remove the original copyright and add my own copyright ?

A:

Unless you replaced all the original code, the original copyright remains. You can add your own (assuming your changes are non-trivial), but you must preserve the original copyright; something like
/*
 * Copyright © ... original holder
 * Copyright © 2016 Anveshak
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */

Section 3 of the EPL makes this explicit:

Contributors may not remove or alter any copyright notices contained within the Program.
Each Contributor must identify itself as the originator of its Contribution, if any, in a manner that reasonably allows subsequent Recipients to identify the originator of the Contribution.

